Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary: [Fields](https://developer.android.com/reference/java/io/ByteArrayInputStream#lfields) \| [Ctors](https://developer.android.com/reference/java/io/ByteArrayInputStream#pubctors) \| [Methods](https://developer.android.com/reference/java/io/ByteArrayInputStream#pubmethods) \| [Inherited Methods](https://developer.android.com/reference/java/io/ByteArrayInputStream#inhmethods)
# ByteArrayInputStream
`
public
class
ByteArrayInputStream
`
`
`
`
extends https://developer.android.com/reference/java/io/InputStream
`
`
`
|---|---|---|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) |||
| ↳ | [java.io.InputStream](https://developer.android.com/reference/java/io/InputStream) ||
| | ↳ | java.io.ByteArrayInputStream |
*** ** * ** ***
A `ByteArrayInputStream` contains
an internal buffer that contains bytes that
may be read from the stream. An internal
counter keeps track of the next byte to
be supplied by the `read` method.
Closing a `ByteArrayInputStream` has no effect. The methods in
this class can be called after the stream has been closed without
generating an `IOException`.
**See also:**
- `https://developer.android.com/reference/java/io/StringBufferInputStream`
## Summary
| ### Fields ||
|---|---|
| ` protected byte[]` | `https://developer.android.com/reference/java/io/ByteArrayInputStream#buf` An array of bytes that was provided by the creator of the stream. |
| ` protected int` | `https://developer.android.com/reference/java/io/ByteArrayInputStream#count` The index one greater than the last valid character in the input stream buffer. |
| ` protected int` | `https://developer.android.com/reference/java/io/ByteArrayInputStream#mark` The currently marked position in the stream. |
| ` protected int` | `https://developer.android.com/reference/java/io/ByteArrayInputStream#pos` The index of the next character to read from the input stream buffer. |
| ### Public constructors ||
|---|---|
| ` https://developer.android.com/reference/java/io/ByteArrayInputStream#ByteArrayInputStream(byte[])(byte[] buf) ` Creates a `ByteArrayInputStream` so that it uses `buf` as its buffer array. |
| ` https://developer.android.com/reference/java/io/ByteArrayInputStream#ByteArrayInputStream(byte[],%20int,%20int)(byte[] buf, int offset, int length) ` Creates `ByteArrayInputStream` that uses `buf` as its buffer array. |
| ### Public methods ||
|---|---|
| ` int` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#available()() ` Returns the number of remaining bytes that can be read (or skipped over) from this input stream. |
| ` void` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#close()() ` Closing a `ByteArrayInputStream` has no effect. |
| ` void` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#mark(int)(int readAheadLimit) ` Set the current marked position in the stream. |
| ` boolean` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#markSupported()() ` Tests if this `InputStream` supports mark/reset. |
| ` int` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#read()() ` Reads the next byte of data from this input stream. |
| ` int` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#read(byte[],%20int,%20int)(byte[] b, int off, int len) ` Reads up to `len` bytes of data into an array of bytes from this input stream. |
| ` byte[]` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#readAllBytes()() ` Reads all remaining bytes from the input stream. |
| ` int` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#readNBytes(byte[],%20int,%20int)(byte[] b, int off, int len) ` Reads the requested number of bytes from the input stream into the given byte array. |
| ` void` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#reset()() ` Resets the buffer to the marked position. |
| ` long` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#skip(long)(long n) ` Skips `n` bytes of input from this input stream. |
| ` long` | ` https://developer.android.com/reference/java/io/ByteArrayInputStream#transferTo(java.io.OutputStream)(https://developer.android.com/reference/java/io/OutputStream out) ` Reads all bytes from this input stream and writes the bytes to the given output stream in the order that they are read. |
| ### Inherited methods |
|---|---|
| From class ` https://developer.android.com/reference/java/io/InputStream ` |---|---| | ` int` | ` https://developer.android.com/reference/java/io/InputStream#available()() ` Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking, which may be 0, or 0 when end of stream is detected. | | ` void` | ` https://developer.android.com/reference/java/io/InputStream#close()() ` Closes this input stream and releases any system resources associated with the stream. | | ` void` | ` https://developer.android.com/reference/java/io/InputStream#mark(int)(int readlimit) ` Marks the current position in this input stream. | | ` boolean` | ` https://developer.android.com/reference/java/io/InputStream#markSupported()() ` Tests if this input stream supports the `mark` and `reset` methods. | | ` static https://developer.android.com/reference/java/io/InputStream` | ` https://developer.android.com/reference/java/io/InputStream#nullInputStream()() ` Returns a new `InputStream` that reads no bytes. | | ` int` | ` https://developer.android.com/reference/java/io/InputStream#read(byte[])(byte[] b) ` Reads some number of bytes from the input stream and stores them into the buffer array `b`. | | ` abstract int` | ` https://developer.android.com/reference/java/io/InputStream#read()() ` Reads the next byte of data from the input stream. | | ` int` | ` https://developer.android.com/reference/java/io/InputStream#read(byte[],%20int,%20int)(byte[] b, int off, int len) ` Reads up to `len` bytes of data from the input stream into an array of bytes. | | ` byte[]` | ` https://developer.android.com/reference/java/io/InputStream#readAllBytes()() ` Reads all remaining bytes from the input stream. | | ` int` | ` https://developer.android.com/reference/java/io/InputStream#readNBytes(byte[],%20int,%20int)(byte[] b, int off, int len) ` Reads the requested number of bytes from the input stream into the given byte array. | | ` byte[]` | ` https://developer.android.com/reference/java/io/InputStream#readNBytes(int)(int len) ` Reads up to a specified number of bytes from the input stream. | | ` void` | ` https://developer.android.com/reference/java/io/InputStream#reset()() ` Repositions this stream to the position at the time the `mark` method was last called on this input stream. | | ` long` | ` https://developer.android.com/reference/java/io/InputStream#skip(long)(long n) ` Skips over and discards `n` bytes of data from this input stream. | | ` void` | ` https://developer.android.com/reference/java/io/InputStream#skipNBytes(long)(long n) ` Skips over and discards exactly `n` bytes of data from this input stream. | | ` long` | ` https://developer.android.com/reference/java/io/InputStream#transferTo(java.io.OutputStream)(https://developer.android.com/reference/java/io/OutputStream out) ` Reads all bytes from this input stream and writes the bytes to the given output stream in the order that they are read. | ||
| From class ` https://developer.android.com/reference/java/lang/Object ` |---|---| | ` https://developer.android.com/reference/java/lang/Object` | ` https://developer.android.com/reference/java/lang/Object#clone()() ` Creates and returns a copy of this object. | | ` boolean` | ` https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object obj) ` Indicates whether some other object is "equal to" this one. | | ` void` | ` 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 https://developer.android.com/reference/java/lang/Class` | ` https://developer.android.com/reference/java/lang/Object#getClass()() ` Returns the runtime class of this `Object`. | | ` int` | ` https://developer.android.com/reference/java/lang/Object#hashCode()() ` Returns a hash code value for the object. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#notify()() ` Wakes up a single thread that is waiting on this object's monitor. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#notifyAll()() ` Wakes up all threads that are waiting on this object's monitor. | | ` https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/java/lang/Object#toString()() ` Returns a string representation of the object. | | ` final void` | ` 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` | ` 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` | ` 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*. | ||
| From interface ` https://developer.android.com/reference/java/io/Closeable ` |---|---| | ` abstract void` | ` https://developer.android.com/reference/java/io/Closeable#close()() ` Closes this stream and releases any system resources associated with it. | ||
| From interface ` https://developer.android.com/reference/java/lang/AutoCloseable ` |---|---| | ` abstract void` | ` https://developer.android.com/reference/java/lang/AutoCloseable#close()() ` Closes this resource, relinquishing any underlying resources. | ||
## Fields
### buf
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected byte[] buf
```
An array of bytes that was provided
by the creator of the stream. Elements `buf[0]`
through `buf[count-1]` are the
only bytes that can ever be read from the
stream; element `buf[pos]` is
the next byte to be read.
### count
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected int count
```
The index one greater than the last valid character in the input
stream buffer.
This value should always be nonnegative
and not larger than the length of `buf`.
It is one greater than the position of
the last byte within `buf` that
can ever be read from the input stream buffer.
### mark
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected int mark
```
The currently marked position in the stream.
ByteArrayInputStream objects are marked at position zero by
default when constructed. They may be marked at another
position within the buffer by the `mark()` method.
The current buffer position is set to this point by the
`reset()` method.
If no mark has been set, then the value of mark is the offset
passed to the constructor (or 0 if the offset was not supplied).
### pos
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected int pos
```
The index of the next character to read from the input stream buffer.
This value should always be nonnegative
and not larger than the value of `count`.
The next byte to be read from the input stream buffer
will be `buf[pos]`.
## Public constructors
### ByteArrayInputStream
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public ByteArrayInputStream (byte[] buf)
```
Creates a `ByteArrayInputStream`
so that it uses `buf` as its
buffer array.
The buffer array is not copied.
The initial value of `pos`
is `0` and the initial value
of `count` is the length of
`buf`.
| Parameters ||
|---|---|
| `buf` | `byte`: the input buffer.
|
### ByteArrayInputStream
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public ByteArrayInputStream (byte[] buf,
int offset,
int length)
```
Creates `ByteArrayInputStream`
that uses `buf` as its
buffer array. The initial value of `pos`
is `offset` and the initial value
of `count` is the minimum of `offset+length`
and `buf.length`.
The buffer array is not copied. The buffer's mark is
set to the specified offset.
| Parameters ||
|---|---|
| `buf` | `byte`: the input buffer.
|
| `offset` | `int`: the offset in the buffer of the first byte to read.
|
| `length` | `int`: the maximum number of bytes to read from the buffer.
|
## Public methods
### available
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int available ()
```
Returns the number of remaining bytes that can be read (or skipped over)
from this input stream.
The value returned is `count - pos`,
which is the number of bytes remaining to be read from the input buffer.
| Returns ||
|---|---|
| `int` | the number of remaining bytes that can be read (or skipped over) from this input stream without blocking.
|
### close
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public void close ()
```
Closing a `ByteArrayInputStream` has no effect. The methods in
this class can be called after the stream has been closed without
generating an `IOException`.
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | |
### mark
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public void mark (int readAheadLimit)
```
Set the current marked position in the stream.
ByteArrayInputStream objects are marked at position zero by
default when constructed. They may be marked at another
position within the buffer by this method.
If no mark has been set, then the value of the mark is the
offset passed to the constructor (or 0 if the offset was not
supplied).
Note: The `readAheadLimit` for this class
has no meaning.
| Parameters ||
|---|---|
| `readAheadLimit` | `int`: the maximum limit of bytes that can be read before the mark position becomes invalid.
|
### markSupported
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public boolean markSupported ()
```
Tests if this `InputStream` supports mark/reset. The
`markSupported` method of `ByteArrayInputStream`
always returns `true`.
| Returns ||
|---|---|
| `boolean` | `true` if this stream instance supports the mark and reset methods; `false` otherwise.
|
### read
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int read ()
```
Reads the next byte of data from this input stream. The value
byte is returned as an `int` in the range
`0` to `255`. If no byte is available
because the end of the stream has been reached, the value
`-1` is returned.
This `read` method
cannot block.
| Returns ||
|---|---|
| `int` | the next byte of data, or `-1` if the end of the stream has been reached.
|
### read
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int read (byte[] b,
int off,
int len)
```
Reads up to `len` bytes of data into an array of bytes from this
input stream. If `pos` equals `count`, then `-1` is
returned to indicate end of file. Otherwise, the number `k` of
bytes read is equal to the smaller of `len` and `count-pos`.
If `k` is positive, then bytes `buf[pos]` through
`buf[pos+k-1]` are copied into `b[off]` through
`b[off+k-1]` in the manner performed by `System.arraycopy`.
The value `k` is added into `pos` and `k` is returned.
This `read` method cannot block.
| Parameters ||
|---|---|
| `b` | `byte`: the buffer into which the data is read.
|
| `off` | `int`: the start offset in the destination array `b`
|
| `len` | `int`: the maximum number of bytes read.
|
| Returns ||
|---|---|
| `int` | the total number of bytes read into the buffer, or `-1` if there is no more data because the end of the stream has been reached.
|
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/lang/IndexOutOfBoundsException` | If `off` is negative, `len` is negative, or `len` is greater than `b.length - off` |
| `https://developer.android.com/reference/java/lang/NullPointerException` | If `b` is `null`. |
### readAllBytes
Added in [API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public byte[] readAllBytes ()
```
Reads all remaining bytes from the input stream. This method blocks until
all remaining bytes have been read and end of stream is detected, or an
exception is thrown. This method does not close the input stream.
When this stream reaches end of stream, further invocations of this
method will return an empty byte array.
Note that this method is intended for simple cases where it is
convenient to read all bytes into a byte array. It is not intended for
reading input streams with large amounts of data.
The behavior for the case where the input stream is *asynchronously closed*, or the thread interrupted during the read, is highly input
stream specific, and therefore not specified.
If an I/O error occurs reading from the input stream, then it may do
so after some, but not all, bytes have been read. Consequently the input
stream may not be at end of stream and may be in an inconsistent state.
It is strongly recommended that the stream be promptly closed if an I/O
error occurs.
| Returns ||
|---|---|
| `byte[]` | a byte array containing the bytes read from this input stream
|
### readNBytes
Added in [API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int readNBytes (byte[] b,
int off,
int len)
```
Reads the requested number of bytes from the input stream into the given
byte array. This method blocks until `len` bytes of input data have
been read, end of stream is detected, or an exception is thrown. The
number of bytes actually read, possibly zero, is returned. This method
does not close the input stream.
In the case where end of stream is reached before `len` bytes
have been read, then the actual number of bytes read will be returned.
When this stream reaches end of stream, further invocations of this
method will return zero.
If `len` is zero, then no bytes are read and `0` is
returned; otherwise, there is an attempt to read up to `len` bytes.
The first byte read is stored into element `b[off]`, the next
one in to `b[off+1]`, and so on. The number of bytes read is, at
most, equal to `len`. Let *k* be the number of bytes actually
read; these bytes will be stored in elements `b[off]` through
`b[off+`*k*`-1]`, leaving elements `b[off+`*k*
`]` through `b[off+len-1]` unaffected.
The behavior for the case where the input stream is *asynchronously closed*, or the thread interrupted during the read, is highly input
stream specific, and therefore not specified.
If an I/O error occurs reading from the input stream, then it may do
so after some, but not all, bytes of `b` have been updated with
data from the input stream. Consequently the input stream and `b`
may be in an inconsistent state. It is strongly recommended that the
stream be promptly closed if an I/O error occurs.
| Parameters ||
|---|---|
| `b` | `byte`: the byte array into which the data is read
|
| `off` | `int`: the start offset in `b` at which the data is written
|
| `len` | `int`: the maximum number of bytes to read
|
| Returns ||
|---|---|
| `int` | the actual number of bytes read into the buffer
|
### reset
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public void reset ()
```
Resets the buffer to the marked position. The marked position
is 0 unless another position was marked or an offset was specified
in the constructor.
### skip
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public long skip (long n)
```
Skips `n` bytes of input from this input stream. Fewer
bytes might be skipped if the end of the input stream is reached.
The actual number `k`
of bytes to be skipped is equal to the smaller
of `n` and `count-pos`.
The value `k` is added into `pos`
and `k` is returned.
| Parameters ||
|---|---|
| `n` | `long`: the number of bytes to be skipped.
|
| Returns ||
|---|---|
| `long` | the actual number of bytes skipped.
|
### transferTo
Added in [API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public long transferTo (OutputStream out)
```
Reads all bytes from this input stream and writes the bytes to the
given output stream in the order that they are read. On return, this
input stream will be at end of stream. This method does not close either
stream.
This method may block indefinitely reading from the input stream, or
writing to the output stream. The behavior for the case where the input
and/or output stream is *asynchronously closed*, or the thread
interrupted during the transfer, is highly input and output stream
specific, and therefore not specified.
If an I/O error occurs reading from the input stream or writing to the
output stream, then it may do so after some bytes have been read or
written. Consequently the input stream may not be at end of stream and
one, or both, streams may be in an inconsistent state. It is strongly
recommended that both streams be promptly closed if an I/O error occurs.
| Parameters ||
|---|---|
| `out` | `OutputStream`: the output stream, non-null
|
| Returns ||
|---|---|
| `long` | the number of bytes transferred
|
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | |