# CharsetEncoder
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
Summary: [Protected Ctors](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#proctors) \| [Methods](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#pubmethods) \| [Protected Methods](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#promethods) \| [Inherited Methods](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#inhmethods)
# CharsetEncoder
`
public
abstract
class
CharsetEncoder
`
`
extends `[Object](https://developer.android.com/reference/java/lang/Object)`
`
`
`
|---|---------------------------------|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) ||
| ↳ | java.nio.charset.CharsetEncoder |
*** ** * ** ***
An engine that can transform a sequence of sixteen-bit Unicode characters into a sequence of
bytes in a specific charset.
The input character sequence is provided in a character buffer or a series
of such buffers. The output byte sequence is written to a byte buffer
or a series of such buffers. An encoder should always be used by making
the following sequence of method invocations, hereinafter referred to as an
*encoding operation*:
1. Reset the encoder via the [reset](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#reset()) method, unless it
has not been used before;
2. Invoke the [encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer)) method zero or more times, as
long as additional input may be available, passing `false` for the
`endOfInput` argument and filling the input buffer and flushing the
output buffer between invocations;
3. Invoke the [encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer)) method one final time, passing
`true` for the `endOfInput` argument; and then
4. Invoke the [flush](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#flush(java.nio.ByteBuffer)) method so that the encoder can
flush any internal state to the output buffer.
Each invocation of the [encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer)) method will encode as many characters as possible from the input buffer, writing the resulting bytes to the output buffer. The [encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer)) method returns when more input is required, when there is not enough room in the output buffer, or when an encoding error has occurred. In each case a [CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) object is returned to describe the reason for termination. An invoker can examine this object and fill the input buffer, flush the output buffer, or attempt to recover from an encoding error, as appropriate, and try again.
There are two general types of encoding errors. If the input character
sequence is not a legal sixteen-bit Unicode sequence then the input is considered *malformed* . If
the input character sequence is legal but cannot be mapped to a valid
byte sequence in the given charset then an *unmappable character* has been encountered.
How an encoding error is handled depends upon the action requested for
that type of error, which is described by an instance of the [CodingErrorAction](https://developer.android.com/reference/java/nio/charset/CodingErrorAction) class. The possible error actions are to [ignore](https://developer.android.com/reference/java/nio/charset/CodingErrorAction#IGNORE) the erroneous input, [report](https://developer.android.com/reference/java/nio/charset/CodingErrorAction#REPORT) the error to the invoker via
the returned [CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) object, or [replace](https://developer.android.com/reference/java/nio/charset/CodingErrorAction#REPLACE) the erroneous input with the current value of the
replacement byte array. The replacement
is initially set to the encoder's default replacement, which often
(but not always) has the initial value `{` `(byte)'?'` `}`;
its value may be changed via the [replaceWith](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#replaceWith(byte[])) method.
The default action for malformed-input and unmappable-character errors
is to [report](https://developer.android.com/reference/java/nio/charset/CodingErrorAction#REPORT) them. The
malformed-input error action may be changed via the [onMalformedInput](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#onMalformedInput(java.nio.charset.CodingErrorAction)) method; the
unmappable-character action may be changed via the [onUnmappableCharacter](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#onUnmappableCharacter(java.nio.charset.CodingErrorAction)) method.
This class is designed to handle many of the details of the encoding
process, including the implementation of error actions. An encoder for a
specific charset, which is a concrete subclass of this class, need only
implement the abstract [encodeLoop](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encodeLoop(java.nio.CharBuffer,%20java.nio.ByteBuffer)) method, which
encapsulates the basic encoding loop. A subclass that maintains internal
state should, additionally, override the [implFlush](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implFlush(java.nio.ByteBuffer)) and
[implReset](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implReset()) methods.
Instances of this class are not safe for use by multiple concurrent
threads.
**See also:**
- [ByteBuffer](https://developer.android.com/reference/java/nio/ByteBuffer)
- [CharBuffer](https://developer.android.com/reference/java/nio/CharBuffer)
- [Charset](https://developer.android.com/reference/java/nio/charset/Charset)
- [CharsetDecoder](https://developer.android.com/reference/java/nio/charset/CharsetDecoder)
## Summary
| ### Protected constructors ||
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---|
| ` `[CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#CharsetEncoder(java.nio.charset.Charset,%20float,%20float))`(`[Charset](https://developer.android.com/reference/java/nio/charset/Charset)` cs, float averageBytesPerChar, float maxBytesPerChar) ` Initializes a new encoder. |
| ` `[CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#CharsetEncoder(java.nio.charset.Charset,%20float,%20float,%20byte[]))`(`[Charset](https://developer.android.com/reference/java/nio/charset/Charset)` cs, float averageBytesPerChar, float maxBytesPerChar, byte[] replacement) ` Initializes a new encoder. |
| ### Public methods ||
|----------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ` final float` | ` `[averageBytesPerChar](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#averageBytesPerChar())`() ` Returns the average number of bytes that will be produced for each character of input. |
| ` boolean` | ` `[canEncode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#canEncode(char))`(char c) ` Tells whether or not this encoder can encode the given character. |
| ` boolean` | ` `[canEncode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#canEncode(java.lang.CharSequence))`(`[CharSequence](https://developer.android.com/reference/java/lang/CharSequence)` cs) ` Tells whether or not this encoder can encode the given character sequence. |
| ` final `[Charset](https://developer.android.com/reference/java/nio/charset/Charset) | ` `[charset](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#charset())`() ` Returns the charset that created this encoder. |
| ` final `[ByteBuffer](https://developer.android.com/reference/java/nio/ByteBuffer) | ` `[encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer))`(`[CharBuffer](https://developer.android.com/reference/java/nio/CharBuffer)` in) ` Convenience method that encodes the remaining content of a single input character buffer into a newly-allocated byte buffer. |
| ` final `[CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) | ` `[encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer,%20java.nio.ByteBuffer,%20boolean))`(`[CharBuffer](https://developer.android.com/reference/java/nio/CharBuffer)` in, `[ByteBuffer](https://developer.android.com/reference/java/nio/ByteBuffer)` out, boolean endOfInput) ` Encodes as many characters as possible from the given input buffer, writing the results to the given output buffer. |
| ` final `[CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) | ` `[flush](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#flush(java.nio.ByteBuffer))`(`[ByteBuffer](https://developer.android.com/reference/java/nio/ByteBuffer)` out) ` Flushes this encoder. |
| ` boolean` | ` `[isLegalReplacement](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#isLegalReplacement(byte[]))`(byte[] repl) ` Tells whether or not the given byte array is a legal replacement value for this encoder. |
| ` `[CodingErrorAction](https://developer.android.com/reference/java/nio/charset/CodingErrorAction) | ` `[malformedInputAction](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#malformedInputAction())`() ` Returns this encoder's current action for malformed-input errors. |
| ` final float` | ` `[maxBytesPerChar](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#maxBytesPerChar())`() ` Returns the maximum number of bytes that will be produced for each character of input. |
| ` final `[CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder) | ` `[onMalformedInput](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#onMalformedInput(java.nio.charset.CodingErrorAction))`(`[CodingErrorAction](https://developer.android.com/reference/java/nio/charset/CodingErrorAction)` newAction) ` Changes this encoder's action for malformed-input errors. |
| ` final `[CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder) | ` `[onUnmappableCharacter](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#onUnmappableCharacter(java.nio.charset.CodingErrorAction))`(`[CodingErrorAction](https://developer.android.com/reference/java/nio/charset/CodingErrorAction)` newAction) ` Changes this encoder's action for unmappable-character errors. |
| ` final `[CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder) | ` `[replaceWith](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#replaceWith(byte[]))`(byte[] newReplacement) ` Changes this encoder's replacement value. |
| ` final byte[]` | ` `[replacement](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#replacement())`() ` Returns this encoder's replacement value. |
| ` final `[CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder) | ` `[reset](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#reset())`() ` Resets this encoder, clearing any internal state. |
| ` `[CodingErrorAction](https://developer.android.com/reference/java/nio/charset/CodingErrorAction) | ` `[unmappableCharacterAction](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#unmappableCharacterAction())`() ` Returns this encoder's current action for unmappable-character errors. |
| ### Protected methods ||
|-------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ` abstract `[CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) | ` `[encodeLoop](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encodeLoop(java.nio.CharBuffer,%20java.nio.ByteBuffer))`(`[CharBuffer](https://developer.android.com/reference/java/nio/CharBuffer)` in, `[ByteBuffer](https://developer.android.com/reference/java/nio/ByteBuffer)` out) ` Encodes one or more characters into one or more bytes. |
| ` `[CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) | ` `[implFlush](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implFlush(java.nio.ByteBuffer))`(`[ByteBuffer](https://developer.android.com/reference/java/nio/ByteBuffer)` out) ` Flushes this encoder. |
| ` void` | ` `[implOnMalformedInput](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implOnMalformedInput(java.nio.charset.CodingErrorAction))`(`[CodingErrorAction](https://developer.android.com/reference/java/nio/charset/CodingErrorAction)` newAction) ` Reports a change to this encoder's malformed-input action. |
| ` void` | ` `[implOnUnmappableCharacter](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implOnUnmappableCharacter(java.nio.charset.CodingErrorAction))`(`[CodingErrorAction](https://developer.android.com/reference/java/nio/charset/CodingErrorAction)` newAction) ` Reports a change to this encoder's unmappable-character action. |
| ` void` | ` `[implReplaceWith](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implReplaceWith(byte[]))`(byte[] newReplacement) ` Reports a change to this encoder's replacement value. |
| ` void` | ` `[implReset](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implReset())`() ` Resets this encoder, clearing any charset-specific internal state. |
| ### Inherited methods |
|-----------------------|---|
| From class ` `[java.lang.Object](https://developer.android.com/reference/java/lang/Object)` ` |--------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` `[Object](https://developer.android.com/reference/java/lang/Object) | ` `[clone](https://developer.android.com/reference/java/lang/Object#clone())`() ` Creates and returns a copy of this object. | | ` boolean` | ` `[equals](https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` obj) ` Indicates whether some other object is "equal to" this one. | | ` void` | ` `[finalize](https://developer.android.com/reference/java/lang/Object#finalize())`() ` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. | | ` final `[Class](https://developer.android.com/reference/java/lang/Class)`` | ` `[getClass](https://developer.android.com/reference/java/lang/Object#getClass())`() ` Returns the runtime class of this `Object`. | | ` int` | ` `[hashCode](https://developer.android.com/reference/java/lang/Object#hashCode())`() ` Returns a hash code value for the object. | | ` final void` | ` `[notify](https://developer.android.com/reference/java/lang/Object#notify())`() ` Wakes up a single thread that is waiting on this object's monitor. | | ` final void` | ` `[notifyAll](https://developer.android.com/reference/java/lang/Object#notifyAll())`() ` Wakes up all threads that are waiting on this object's monitor. | | ` `[String](https://developer.android.com/reference/java/lang/String) | ` `[toString](https://developer.android.com/reference/java/lang/Object#toString())`() ` Returns a string representation of the object. | | ` final void` | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait(long,%20int))`(long timeoutMillis, int nanos) ` Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait(long))`(long timeoutMillis) ` Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait())`() ` Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*. | ||
## Protected constructors
### CharsetEncoder
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected CharsetEncoder (Charset cs,
float averageBytesPerChar,
float maxBytesPerChar)
```
Initializes a new encoder. The new encoder will have the given
bytes-per-char values and its replacement will be the
byte array `{` `(byte)'?'` `}`.
| Parameters ||
|-----------------------|-------------------------------------------------------------------------------------------------------------------------------|
| `cs` | `Charset`: The charset that created this encoder
|
| `averageBytesPerChar` | `float`: A positive float value indicating the expected number of bytes that will be produced for each input character
|
| `maxBytesPerChar` | `float`: A positive float value indicating the maximum number of bytes that will be produced for each input character
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|----------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | If the preconditions on the parameters do not hold |
### CharsetEncoder
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected CharsetEncoder (Charset cs,
float averageBytesPerChar,
float maxBytesPerChar,
byte[] replacement)
```
Initializes a new encoder. The new encoder will have the given
bytes-per-char and replacement values.
| Parameters ||
|-----------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `cs` | `Charset`: The charset that created this encoder
|
| `averageBytesPerChar` | `float`: A positive float value indicating the expected number of bytes that will be produced for each input character
|
| `maxBytesPerChar` | `float`: A positive float value indicating the maximum number of bytes that will be produced for each input character
|
| `replacement` | `byte`: The initial replacement; must not be `null`, must have non-zero length, must not be longer than maxBytesPerChar, and must be [legal](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#isLegalReplacement(byte[]))
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|----------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | If the preconditions on the parameters do not hold |
## Public methods
### averageBytesPerChar
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final float averageBytesPerChar ()
```
Returns the average number of bytes that will be produced for each
character of input. This heuristic value may be used to estimate the size
of the output buffer required for a given input sequence.
| Returns ||
|---------|--------------------------------------------------------------------|
| `float` | The average number of bytes produced per character of input
|
### canEncode
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public boolean canEncode (char c)
```
Tells whether or not this encoder can encode the given character.
This method returns `false` if the given character is a
surrogate character; such characters can be interpreted only when they
are members of a pair consisting of a high surrogate followed by a low
surrogate. The [canEncode(CharSequence)](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#canEncode(java.lang.CharSequence)) method may be used to test whether or not a
character sequence can be encoded.
This method may modify this encoder's state; it should therefore not
be invoked if an [encoding operation](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#steps) is already in
progress.
The default implementation of this method is not very efficient; it
should generally be overridden to improve performance.
| Parameters ||
|-----|------------------------------------|
| `c` | `char`: The given character
|
| Returns ||
|-----------|----------------------------------------------------------------------------|
| `boolean` | `true` if, and only if, this encoder can encode the given character
|
| Throws ||
|--------------------------------------------------------------------------------------------------|-------------------------------------------------|
| [IllegalStateException](https://developer.android.com/reference/java/lang/IllegalStateException) | If an encoding operation is already in progress |
### canEncode
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public boolean canEncode (CharSequence cs)
```
Tells whether or not this encoder can encode the given character
sequence.
If this method returns `false` for a particular character
sequence then more information about why the sequence cannot be encoded
may be obtained by performing a full [encoding
operation](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#steps).
This method may modify this encoder's state; it should therefore not
be invoked if an encoding operation is already in progress.
The default implementation of this method is not very efficient; it
should generally be overridden to improve performance.
| Parameters ||
|------|-----------------------------------------------------|
| `cs` | `CharSequence`: The given character sequence
|
| Returns ||
|-----------|----------------------------------------------------------------------------------------------------------------------------------------------------|
| `boolean` | `true` if, and only if, this encoder can encode the given character without throwing any exceptions and without performing any replacements
|
| Throws ||
|--------------------------------------------------------------------------------------------------|-------------------------------------------------|
| [IllegalStateException](https://developer.android.com/reference/java/lang/IllegalStateException) | If an encoding operation is already in progress |
### charset
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final Charset charset ()
```
Returns the charset that created this encoder.
| Returns ||
|-----------------------------------------------------------------------------|-------------------------------|
| [Charset](https://developer.android.com/reference/java/nio/charset/Charset) | This encoder's charset
|
### encode
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final ByteBuffer encode (CharBuffer in)
```
Convenience method that encodes the remaining content of a single input
character buffer into a newly-allocated byte buffer.
This method implements an entire [encoding
operation](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#steps); that is, it resets this encoder, then it encodes the
characters in the given character buffer, and finally it flushes this
encoder. This method should therefore not be invoked if an encoding
operation is already in progress.
| Parameters ||
|------|-------------------------------------------------|
| `in` | `CharBuffer`: The input character buffer
|
| Returns ||
|---------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [ByteBuffer](https://developer.android.com/reference/java/nio/ByteBuffer) | A newly-allocated byte buffer containing the result of the encoding operation. The buffer's position will be zero and its limit will follow the last byte written.
|
| Throws ||
|-----------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [IllegalStateException](https://developer.android.com/reference/java/lang/IllegalStateException) | If an encoding operation is already in progress |
| [MalformedInputException](https://developer.android.com/reference/java/nio/charset/MalformedInputException) | If the character sequence starting at the input buffer's current position is not a legal sixteen-bit Unicode sequence and the current malformed-input action is [CodingErrorAction.REPORT](https://developer.android.com/reference/java/nio/charset/CodingErrorAction#REPORT) |
| [UnmappableCharacterException](https://developer.android.com/reference/java/nio/charset/UnmappableCharacterException) | If the character sequence starting at the input buffer's current position cannot be mapped to an equivalent byte sequence and the current unmappable-character action is [CodingErrorAction.REPORT](https://developer.android.com/reference/java/nio/charset/CodingErrorAction#REPORT) |
| [CoderMalfunctionError](https://developer.android.com/reference/java/nio/charset/CoderMalfunctionError) | If an invocation of the encodeLoop method threw an unexpected exception |
| [NullPointerException](https://developer.android.com/reference/java/lang/NullPointerException) | if input buffer is null |
| [CharacterCodingException](https://developer.android.com/reference/java/nio/charset/CharacterCodingException) | |
### encode
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final CoderResult encode (CharBuffer in,
ByteBuffer out,
boolean endOfInput)
```
Encodes as many characters as possible from the given input buffer,
writing the results to the given output buffer.
The buffers are read from, and written to, starting at their current
positions. At most [in.remaining()](https://developer.android.com/reference/java/nio/Buffer#remaining()) characters
will be read and at most [out.remaining()](https://developer.android.com/reference/java/nio/Buffer#remaining())
bytes will be written. The buffers' positions will be advanced to
reflect the characters read and the bytes written, but their marks and
limits will not be modified.
In addition to reading characters from the input buffer and writing
bytes to the output buffer, this method returns a [CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult)
object to describe its reason for termination:
- [CoderResult.UNDERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#UNDERFLOW) indicates that as much of the
input buffer as possible has been encoded. If there is no further
input then the invoker can proceed to the next step of the
[encoding operation](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#steps). Otherwise this method
should be invoked again with further input.
- [CoderResult.OVERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#OVERFLOW) indicates that there is
insufficient space in the output buffer to encode any more characters.
This method should be invoked again with an output buffer that has
more [remaining](https://developer.android.com/reference/java/nio/Buffer#remaining()) bytes. This is
typically done by draining any encoded bytes from the output
buffer.
- A [malformed-input](https://developer.android.com/reference/java/nio/charset/CoderResult#malformedForLength(int)) result indicates that a malformed-input
error has been detected. The malformed characters begin at the input
buffer's (possibly incremented) position; the number of malformed
characters may be determined by invoking the result object's [length](https://developer.android.com/reference/java/nio/charset/CoderResult#length()) method. This case applies only if the
[malformed action](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#onMalformedInput(java.nio.charset.CodingErrorAction)) of this encoder
is [CodingErrorAction.REPORT](https://developer.android.com/reference/java/nio/charset/CodingErrorAction#REPORT); otherwise the malformed input
will be ignored or replaced, as requested.
- An [unmappable-character](https://developer.android.com/reference/java/nio/charset/CoderResult#unmappableForLength(int)) result indicates that an
unmappable-character error has been detected. The characters that
encode the unmappable character begin at the input buffer's (possibly
incremented) position; the number of such characters may be determined
by invoking the result object's [length](https://developer.android.com/reference/java/nio/charset/CoderResult#length())
method. This case applies only if the [unmappable action](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#onUnmappableCharacter(java.nio.charset.CodingErrorAction)) of this encoder is [CodingErrorAction.REPORT](https://developer.android.com/reference/java/nio/charset/CodingErrorAction#REPORT); otherwise the unmappable character will be
ignored or replaced, as requested.
In any case, if this method is to be reinvoked in the same encoding operation then care should be taken to preserve any characters remaining in the input buffer so that they are available to the next invocation.
The `endOfInput` parameter advises this method as to whether
the invoker can provide further input beyond that contained in the given
input buffer. If there is a possibility of providing additional input
then the invoker should pass `false` for this parameter; if there
is no possibility of providing further input then the invoker should
pass `true`. It is not erroneous, and in fact it is quite
common, to pass `false` in one invocation and later discover that
no further input was actually available. It is critical, however, that
the final invocation of this method in a sequence of invocations always
pass `true` so that any remaining unencoded input will be treated
as being malformed.
This method works by invoking the [encodeLoop](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encodeLoop(java.nio.CharBuffer,%20java.nio.ByteBuffer))
method, interpreting its results, handling error conditions, and
reinvoking it as necessary.
| Parameters ||
|--------------|-----------------------------------------------------------------------------------------------------------------------------------|
| `in` | `CharBuffer`: The input character buffer
|
| `out` | `ByteBuffer`: The output byte buffer
|
| `endOfInput` | `boolean`: `true` if, and only if, the invoker can provide no additional input characters beyond those in the given buffer
|
| Returns ||
|-------------------------------------------------------------------------------------|--------------------------------------------------------------------|
| [CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) | A coder-result object describing the reason for termination
|
| Throws ||
|---------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [IllegalStateException](https://developer.android.com/reference/java/lang/IllegalStateException) | If an encoding operation is already in progress and the previous step was an invocation neither of the [reset](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#reset()) method, nor of this method with a value of `false` for the `endOfInput` parameter, nor of this method with a value of `true` for the `endOfInput` parameter but a return value indicating an incomplete encoding operation |
| [CoderMalfunctionError](https://developer.android.com/reference/java/nio/charset/CoderMalfunctionError) | If an invocation of the encodeLoop method threw an unexpected exception |
| [NullPointerException](https://developer.android.com/reference/java/lang/NullPointerException) | if input or output buffer is null |
### flush
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final CoderResult flush (ByteBuffer out)
```
Flushes this encoder.
Some encoders maintain internal state and may need to write some
final bytes to the output buffer once the overall input sequence has
been read.
Any additional output is written to the output buffer beginning at
its current position. At most [out.remaining()](https://developer.android.com/reference/java/nio/Buffer#remaining())
bytes will be written. The buffer's position will be advanced
appropriately, but its mark and limit will not be modified.
If this method completes successfully then it returns [CoderResult.UNDERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#UNDERFLOW). If there is insufficient room in the output
buffer then it returns [CoderResult.OVERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#OVERFLOW). If this happens
then this method must be invoked again, with an output buffer that has
more room, in order to complete the current [encoding
operation](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#steps).
If this encoder has already been flushed then invoking this method
has no effect.
This method invokes the [implFlush](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implFlush(java.nio.ByteBuffer)) method to
perform the actual flushing operation.
| Parameters ||
|-------|---------------------------------------------|
| `out` | `ByteBuffer`: The output byte buffer
|
| Returns ||
|-------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) | A coder-result object, either [CoderResult.UNDERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#UNDERFLOW) or [CoderResult.OVERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#OVERFLOW)
|
| Throws ||
|--------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [IllegalStateException](https://developer.android.com/reference/java/lang/IllegalStateException) | If the previous step of the current encoding operation was an invocation neither of the [flush](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#flush(java.nio.ByteBuffer)) method nor of the three-argument [encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer,%20java.nio.ByteBuffer,%20boolean)) method with a value of `true` for the `endOfInput` parameter |
### isLegalReplacement
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public boolean isLegalReplacement (byte[] repl)
```
Tells whether or not the given byte array is a legal replacement value
for this encoder.
A replacement is legal if, and only if, it is a legal sequence of
bytes in this encoder's charset; that is, it must be possible to decode
the replacement into one or more sixteen-bit Unicode characters.
The default implementation of this method is not very efficient; it
should generally be overridden to improve performance.
| Parameters ||
|--------|--------------------------------------------|
| `repl` | `byte`: The byte array to be tested
|
| Returns ||
|-----------|---------------------------------------------------------------------------------------------------|
| `boolean` | `true` if, and only if, the given byte array is a legal replacement value for this encoder
|
### malformedInputAction
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public CodingErrorAction malformedInputAction ()
```
Returns this encoder's current action for malformed-input errors.
| Returns ||
|-------------------------------------------------------------------------------------------------|------------------------------------------------------------------|
| [CodingErrorAction](https://developer.android.com/reference/java/nio/charset/CodingErrorAction) | The current malformed-input action, which is never `null`
|
### maxBytesPerChar
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final float maxBytesPerChar ()
```
Returns the maximum number of bytes that will be produced for each
character of input. This value may be used to compute the worst-case size
of the output buffer required for a given input sequence. This value
accounts for any necessary content-independent prefix or suffix
bytes, such as byte-order marks.
| Returns ||
|---------|---------------------------------------------------------------------------------|
| `float` | The maximum number of bytes that will be produced per character of input
|
### onMalformedInput
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final CharsetEncoder onMalformedInput (CodingErrorAction newAction)
```
Changes this encoder's action for malformed-input errors.
This method invokes the [implOnMalformedInput](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implOnMalformedInput(java.nio.charset.CodingErrorAction)) method, passing the new action.
| Parameters ||
|-------------|----------------------------------------------------------------|
| `newAction` | `CodingErrorAction`: The new action; must not be `null`
|
| Returns ||
|-------------------------------------------------------------------------------------------|---------------------|
| [CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder) | This encoder
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|----------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | If the precondition on the parameter does not hold |
### onUnmappableCharacter
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final CharsetEncoder onUnmappableCharacter (CodingErrorAction newAction)
```
Changes this encoder's action for unmappable-character errors.
This method invokes the [implOnUnmappableCharacter](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implOnUnmappableCharacter(java.nio.charset.CodingErrorAction)) method, passing the new action.
| Parameters ||
|-------------|----------------------------------------------------------------|
| `newAction` | `CodingErrorAction`: The new action; must not be `null`
|
| Returns ||
|-------------------------------------------------------------------------------------------|---------------------|
| [CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder) | This encoder
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|----------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | If the precondition on the parameter does not hold |
### replaceWith
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final CharsetEncoder replaceWith (byte[] newReplacement)
```
Changes this encoder's replacement value.
This method invokes the [implReplaceWith](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implReplaceWith(byte[]))
method, passing the new replacement, after checking that the new
replacement is acceptable.
| Parameters ||
|------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `newReplacement` | `byte`: The new replacement; must not be `null`, must have non-zero length, must not be longer than the value returned by the [maxBytesPerChar](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#maxBytesPerChar()) method, and must be [legal](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#isLegalReplacement(byte[]))
|
| Returns ||
|-------------------------------------------------------------------------------------------|---------------------|
| [CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder) | This encoder
|
| Throws ||
|--------------------------------------------------------------------------------------------------------|---------------------------------------------------|
| [IllegalArgumentException](https://developer.android.com/reference/java/lang/IllegalArgumentException) | If the preconditions on the parameter do not hold |
### replacement
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final byte[] replacement ()
```
Returns this encoder's replacement value.
| Returns ||
|----------|-------------------------------------------------------------------------------------|
| `byte[]` | This encoder's current replacement, which is never `null` and is never empty
|
### reset
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public final CharsetEncoder reset ()
```
Resets this encoder, clearing any internal state.
This method resets charset-independent state and also invokes the
[implReset](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#implReset()) method in order to perform any
charset-specific reset actions.
| Returns ||
|-------------------------------------------------------------------------------------------|---------------------|
| [CharsetEncoder](https://developer.android.com/reference/java/nio/charset/CharsetEncoder) | This encoder
|
### unmappableCharacterAction
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public CodingErrorAction unmappableCharacterAction ()
```
Returns this encoder's current action for unmappable-character errors.
| Returns ||
|-------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------|
| [CodingErrorAction](https://developer.android.com/reference/java/nio/charset/CodingErrorAction) | The current unmappable-character action, which is never `null`
|
## Protected methods
### encodeLoop
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected abstract CoderResult encodeLoop (CharBuffer in,
ByteBuffer out)
```
Encodes one or more characters into one or more bytes.
This method encapsulates the basic encoding loop, encoding as many
characters as possible until it either runs out of input, runs out of room
in the output buffer, or encounters an encoding error. This method is
invoked by the [encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer)) method, which handles result
interpretation and error recovery.
The buffers are read from, and written to, starting at their current
positions. At most [in.remaining()](https://developer.android.com/reference/java/nio/Buffer#remaining()) characters
will be read, and at most [out.remaining()](https://developer.android.com/reference/java/nio/Buffer#remaining())
bytes will be written. The buffers' positions will be advanced to
reflect the characters read and the bytes written, but their marks and
limits will not be modified.
This method returns a [CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) object to describe its
reason for termination, in the same manner as the [encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer))
method. Most implementations of this method will handle encoding errors
by returning an appropriate result object for interpretation by the
[encode](https://developer.android.com/reference/java/nio/charset/CharsetEncoder#encode(java.nio.CharBuffer)) method. An optimized implementation may instead
examine the relevant error action and implement that action itself.
An implementation of this method may perform arbitrary lookahead by
returning [CoderResult.UNDERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#UNDERFLOW) until it receives sufficient
input.
| Parameters ||
|-------|-------------------------------------------------|
| `in` | `CharBuffer`: The input character buffer
|
| `out` | `ByteBuffer`: The output byte buffer
|
| Returns ||
|-------------------------------------------------------------------------------------|--------------------------------------------------------------------|
| [CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) | A coder-result object describing the reason for termination
|
### implFlush
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected CoderResult implFlush (ByteBuffer out)
```
Flushes this encoder.
The default implementation of this method does nothing, and always
returns [CoderResult.UNDERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#UNDERFLOW). This method should be overridden
by encoders that may need to write final bytes to the output buffer
once the entire input sequence has been read.
| Parameters ||
|-------|---------------------------------------------|
| `out` | `ByteBuffer`: The output byte buffer
|
| Returns ||
|-------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [CoderResult](https://developer.android.com/reference/java/nio/charset/CoderResult) | A coder-result object, either [CoderResult.UNDERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#UNDERFLOW) or [CoderResult.OVERFLOW](https://developer.android.com/reference/java/nio/charset/CoderResult#OVERFLOW)
|
### implOnMalformedInput
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected void implOnMalformedInput (CodingErrorAction newAction)
```
Reports a change to this encoder's malformed-input action.
The default implementation of this method does nothing. This method
should be overridden by encoders that require notification of changes to
the malformed-input action.
| Parameters ||
|-------------|--------------------------------------------|
| `newAction` | `CodingErrorAction`: The new action
|
### implOnUnmappableCharacter
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected void implOnUnmappableCharacter (CodingErrorAction newAction)
```
Reports a change to this encoder's unmappable-character action.
The default implementation of this method does nothing. This method
should be overridden by encoders that require notification of changes to
the unmappable-character action.
| Parameters ||
|-------------|--------------------------------------------|
| `newAction` | `CodingErrorAction`: The new action
|
### implReplaceWith
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected void implReplaceWith (byte[] newReplacement)
```
Reports a change to this encoder's replacement value.
The default implementation of this method does nothing. This method
should be overridden by encoders that require notification of changes to
the replacement.
| Parameters ||
|------------------|--------------------------------------|
| `newReplacement` | `byte`: The replacement value
|
### implReset
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected void implReset ()
```
Resets this encoder, clearing any charset-specific internal state.
The default implementation of this method does nothing. This method
should be overridden by encoders that maintain internal state.