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/FilterReader#lfields) \| [Inherited Fields](https://developer.android.com/reference/java/io/FilterReader#inhfields) \| [Protected Ctors](https://developer.android.com/reference/java/io/FilterReader#proctors) \| [Methods](https://developer.android.com/reference/java/io/FilterReader#pubmethods) \| [Inherited Methods](https://developer.android.com/reference/java/io/FilterReader#inhmethods)
# FilterReader
` public abstract class FilterReader `
` ` ` extends https://developer.android.com/reference/java/io/Reader ` ` `
|---|---|---|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) |||
| ↳ | [java.io.Reader](https://developer.android.com/reference/java/io/Reader) ||
| | ↳ | java.io.FilterReader |
Known direct subclasses [PushbackReader](https://developer.android.com/reference/java/io/PushbackReader) [PushbackReader](https://developer.android.com/reference/java/io/PushbackReader) A character-stream reader that allows characters to be pushed back into the stream.
*** ** * ** ***
Abstract class for reading filtered character streams. The abstract class `FilterReader` itself provides default methods that pass all requests to the contained stream. Subclasses of `FilterReader` should override some of these methods and may also provide additional methods and fields.
## Summary
| ### Fields ||
|---|---|
| ` protected https://developer.android.com/reference/java/io/Reader` | `https://developer.android.com/reference/java/io/FilterReader#in` The underlying character-input stream. |
### Inherited fields
From class `https://developer.android.com/reference/java/io/Reader` ` protected https://developer.android.com/reference/java/lang/Object` `https://developer.android.com/reference/java/io/Reader#lock`
The object used to synchronize operations on this stream.
| ### Protected constructors ||
|---|---|
| ` https://developer.android.com/reference/java/io/FilterReader#FilterReader(java.io.Reader)(https://developer.android.com/reference/java/io/Reader in) ` Creates a new filtered reader. |
| ### Public methods ||
|---|---|
| ` void` | ` https://developer.android.com/reference/java/io/FilterReader#close()() ` Closes the stream and releases any system resources associated with it. |
| ` void` | ` https://developer.android.com/reference/java/io/FilterReader#mark(int)(int readAheadLimit) ` Marks the present position in the stream. |
| ` boolean` | ` https://developer.android.com/reference/java/io/FilterReader#markSupported()() ` Tells whether this stream supports the mark() operation. |
| ` int` | ` https://developer.android.com/reference/java/io/FilterReader#read()() ` Reads a single character. |
| ` int` | ` https://developer.android.com/reference/java/io/FilterReader#read(char[],%20int,%20int)(char[] cbuf, int off, int len) ` Reads characters into a portion of an array. |
| ` boolean` | ` https://developer.android.com/reference/java/io/FilterReader#ready()() ` Tells whether this stream is ready to be read. |
| ` void` | ` https://developer.android.com/reference/java/io/FilterReader#reset()() ` Resets the stream. |
| ` long` | ` https://developer.android.com/reference/java/io/FilterReader#skip(long)(long n) ` Skips characters. |
### Inherited methods
From class ` https://developer.android.com/reference/java/io/Reader ` ` abstract void` ` https://developer.android.com/reference/java/io/Reader#close()() `
Closes the stream and releases any system resources associated with it.
` void` ` https://developer.android.com/reference/java/io/Reader#mark(int)(int readAheadLimit) `
Marks the present position in the stream.
` boolean` ` https://developer.android.com/reference/java/io/Reader#markSupported()() `
Tells whether this stream supports the mark() operation.
` static https://developer.android.com/reference/java/io/Reader` ` https://developer.android.com/reference/java/io/Reader#nullReader()() `
Returns a new `Reader` that reads no characters.
` int` ` https://developer.android.com/reference/java/io/Reader#read()() `
Reads a single character.
` abstract int` ` https://developer.android.com/reference/java/io/Reader#read(char[],%20int,%20int)(char[] cbuf, int off, int len) `
Reads characters into a portion of an array.
` int` ` https://developer.android.com/reference/java/io/Reader#read(char[])(char[] cbuf) `
Reads characters into an array.
` int` ` https://developer.android.com/reference/java/io/Reader#read(java.nio.CharBuffer)(https://developer.android.com/reference/java/nio/CharBuffer target) `
Attempts to read characters into the specified character buffer.
` boolean` ` https://developer.android.com/reference/java/io/Reader#ready()() `
Tells whether this stream is ready to be read.
` void` ` https://developer.android.com/reference/java/io/Reader#reset()() `
Resets the stream.
` long` ` https://developer.android.com/reference/java/io/Reader#skip(long)(long n) `
Skips characters.
` long` ` https://developer.android.com/reference/java/io/Reader#transferTo(java.io.Writer)(https://developer.android.com/reference/java/io/Writer out) `
Reads all characters from this reader and writes the characters to the given writer 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/Readable ` ` abstract int` ` https://developer.android.com/reference/java/lang/Readable#read(java.nio.CharBuffer)(https://developer.android.com/reference/java/nio/CharBuffer cb) `
Attempts to read characters into the specified character buffer.
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
### in
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected Reader in
```
The underlying character-input stream.
## Protected constructors
### FilterReader
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
protected FilterReader (Reader in)
```
Creates a new filtered reader.
| Parameters ||
|---|---|
| `in` | `Reader`: a Reader object providing the underlying stream.
|
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/lang/NullPointerException` | if `in` is `null` |
## Public methods
### close
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public void close ()
```
Closes the stream and releases any system resources associated with it. Once the stream has been closed, further read(), ready(), mark(), reset(), or skip() invocations will throw an IOException. Closing a previously closed stream has no effect.
| 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)
```
Marks the present position in the stream.
| Parameters ||
|---|---|
| `readAheadLimit` | `int`: Limit on the number of characters that may be read while still preserving the mark. After reading this many characters, attempting to reset the stream may fail.
|
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | If an I/O error occurs |
### markSupported
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public boolean markSupported ()
```
Tells whether this stream supports the mark() operation.
| Returns ||
|---|---|
| `boolean` | true if and only if this stream supports the mark operation.
|
### read
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int read ()
```
Reads a single character.
| Returns ||
|---|---|
| `int` | The character read, as an integer in the range 0 to 65535 (`0x00-0xffff`), or -1 if the end of the stream has been reached
|
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | If an I/O error occurs |
### read
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public int read (char[] cbuf,
int off,
int len)
```
Reads characters into a portion of an array.
| Parameters ||
|---|---|
| `cbuf` | `char`: Destination buffer
|
| `off` | `int`: Offset at which to start storing characters
|
| `len` | `int`: Maximum number of characters to read
|
| Returns ||
|---|---|
| `int` | The number of characters read, or -1 if the end of the stream has been reached
|
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | If an I/O error occurs |
| `https://developer.android.com/reference/java/lang/IndexOutOfBoundsException` | |
### ready
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public boolean ready ()
```
Tells whether this stream is ready to be read.
| Returns ||
|---|---|
| `boolean` | True if the next read() is guaranteed not to block for input, false otherwise. Note that returning false does not guarantee that the next read will block.
|
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | If an I/O error occurs |
### reset
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public void reset ()
```
Resets the stream.
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | If an I/O error occurs |
### skip
Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public long skip (long n)
```
Skips characters.
| Parameters ||
|---|---|
| `n` | `long`: The number of characters to skip
|
| Returns ||
|---|---|
| `long` | The number of characters actually skipped
|
| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | If an I/O error occurs |