# ObjectInput
Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
Summary:[Methods](https://developer.android.com/reference/java/io/ObjectInput#pubmethods)\|[Inherited Methods](https://developer.android.com/reference/java/io/ObjectInput#inhmethods)
# ObjectInput
`
public
interface
ObjectInput
`
`
implements
`[AutoCloseable](https://developer.android.com/reference/java/lang/AutoCloseable)`,
`[DataInput](https://developer.android.com/reference/java/io/DataInput)`
`
|---------------------|
| java.io.ObjectInput |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Known indirect subclasses [ObjectInputStream](https://developer.android.com/reference/java/io/ObjectInputStream) |----------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------| | [ObjectInputStream](https://developer.android.com/reference/java/io/ObjectInputStream) | An ObjectInputStream deserializes primitive data and objects previously written using an ObjectOutputStream. | |
*** ** * ** ***
ObjectInput extends the DataInput interface to include the reading of objects. DataInput includes methods for the input of primitive types, ObjectInput extends that interface to include objects, arrays, and Strings.
**See also:**
- [InputStream](https://developer.android.com/reference/java/io/InputStream)
- [ObjectOutputStream](https://developer.android.com/reference/java/io/ObjectOutputStream)
- [ObjectInputStream](https://developer.android.com/reference/java/io/ObjectInputStream)
## Summary
| ### Public methods ||
|--------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ` abstract int` | ` `[available](https://developer.android.com/reference/java/io/ObjectInput#available())`() ` Returns the number of bytes that can be read without blocking. |
| ` abstract void` | ` `[close](https://developer.android.com/reference/java/io/ObjectInput#close())`() ` Closes the input stream. |
| ` abstract int` | ` `[read](https://developer.android.com/reference/java/io/ObjectInput#read())`() ` Reads a byte of data. |
| ` abstract int` | ` `[read](https://developer.android.com/reference/java/io/ObjectInput#read(byte[],%20int,%20int))`(byte[] b, int off, int len) ` Reads into an array of bytes. |
| ` abstract int` | ` `[read](https://developer.android.com/reference/java/io/ObjectInput#read(byte[]))`(byte[] b) ` Reads into an array of bytes. |
| ` abstract `[Object](https://developer.android.com/reference/java/lang/Object) | ` `[readObject](https://developer.android.com/reference/java/io/ObjectInput#readObject())`() ` Read and return an object. |
| ` abstract long` | ` `[skip](https://developer.android.com/reference/java/io/ObjectInput#skip(long))`(long n) ` Skips n bytes of input. |
| ### Inherited methods |
|-----------------------|---|
| From interface` `[java.lang.AutoCloseable](https://developer.android.com/reference/java/lang/AutoCloseable)` ` |------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------| | ` abstract void` | ` `[close](https://developer.android.com/reference/java/lang/AutoCloseable#close())`() ` Closes this resource, relinquishing any underlying resources. | ||
| From interface` `[java.io.DataInput](https://developer.android.com/reference/java/io/DataInput)` ` |--------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` abstract boolean` | ` `[readBoolean](https://developer.android.com/reference/java/io/DataInput#readBoolean())`() ` Reads one input byte and returns`true`if that byte is nonzero,`false`if that byte is zero. | | ` abstract byte` | ` `[readByte](https://developer.android.com/reference/java/io/DataInput#readByte())`() ` Reads and returns one input byte. | | ` abstract char` | ` `[readChar](https://developer.android.com/reference/java/io/DataInput#readChar())`() ` Reads two input bytes and returns a`char`value. | | ` abstract double` | ` `[readDouble](https://developer.android.com/reference/java/io/DataInput#readDouble())`() ` Reads eight input bytes and returns a`double`value. | | ` abstract float` | ` `[readFloat](https://developer.android.com/reference/java/io/DataInput#readFloat())`() ` Reads four input bytes and returns a`float`value. | | ` abstract void` | ` `[readFully](https://developer.android.com/reference/java/io/DataInput#readFully(byte[]))`(byte[] b) ` Reads some bytes from an input stream and stores them into the buffer array`b`. | | ` abstract void` | ` `[readFully](https://developer.android.com/reference/java/io/DataInput#readFully(byte[],%20int,%20int))`(byte[] b, int off, int len) ` Reads`len`bytes from an input stream. | | ` abstract int` | ` `[readInt](https://developer.android.com/reference/java/io/DataInput#readInt())`() ` Reads four input bytes and returns an`int`value. | | ` abstract `[String](https://developer.android.com/reference/java/lang/String) | ` `[readLine](https://developer.android.com/reference/java/io/DataInput#readLine())`() ` Reads the next line of text from the input stream. | | ` abstract long` | ` `[readLong](https://developer.android.com/reference/java/io/DataInput#readLong())`() ` Reads eight input bytes and returns a`long`value. | | ` abstract short` | ` `[readShort](https://developer.android.com/reference/java/io/DataInput#readShort())`() ` Reads two input bytes and returns a`short`value. | | ` abstract `[String](https://developer.android.com/reference/java/lang/String) | ` `[readUTF](https://developer.android.com/reference/java/io/DataInput#readUTF())`() ` Reads in a string that has been encoded using a[modified UTF-8](https://developer.android.com/reference/java/io/ObjectInput#modified-utf-8)format. | | ` abstract int` | ` `[readUnsignedByte](https://developer.android.com/reference/java/io/DataInput#readUnsignedByte())`() ` Reads one input byte, zero-extends it to type`int`, and returns the result, which is therefore in the range`0`through`255`. | | ` abstract int` | ` `[readUnsignedShort](https://developer.android.com/reference/java/io/DataInput#readUnsignedShort())`() ` Reads two input bytes and returns an`int`value in the range`0`through`65535`. | | ` abstract int` | ` `[skipBytes](https://developer.android.com/reference/java/io/DataInput#skipBytes(int))`(int n) ` Makes an attempt to skip over`n`bytes of data from the input stream, discarding the skipped bytes. | ||
## Public methods
### available
Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public abstract int available ()
```
Returns the number of bytes that can be read without blocking.
| Returns ||
|-------|---------------------------------------|
| `int` | the number of available bytes.
|
| Throws ||
|----------------------------------------------------------------------------|-------------------------------|
| [IOException](https://developer.android.com/reference/java/io/IOException) | If an I/O error has occurred. |
### close
Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public abstract void close ()
```
Closes the input stream. Must be called to release any resources associated with the stream.
| Throws ||
|----------------------------------------------------------------------------|-------------------------------|
| [IOException](https://developer.android.com/reference/java/io/IOException) | If an I/O error has occurred. |
### read
Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public abstract int read ()
```
Reads a byte of data. This method will block if no input is available.
| Returns ||
|-------|------------------------------------------------------------------|
| `int` | the byte read, or -1 if the end of the stream is reached.
|
| Throws ||
|----------------------------------------------------------------------------|-------------------------------|
| [IOException](https://developer.android.com/reference/java/io/IOException) | If an I/O error has occurred. |
### read
Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public abstract int read (byte[] b,
int off,
int len)
```
Reads into an array of bytes. This method will block until some input is available.
| Parameters ||
|-------|-------------------------------------------------------|
| `b` | `byte`: the buffer into which the data is read
|
| `off` | `int`: the start offset of the data
|
| `len` | `int`: the maximum number of bytes read
|
| Returns ||
|-------|-----------------------------------------------------------------------------------------------|
| `int` | the actual number of bytes read, -1 is returned when the end of the stream is reached.
|
| Throws ||
|----------------------------------------------------------------------------|-------------------------------|
| [IOException](https://developer.android.com/reference/java/io/IOException) | If an I/O error has occurred. |
### read
Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public abstract int read (byte[] b)
```
Reads into an array of bytes. This method will block until some input is available.
| Parameters ||
|-----|-------------------------------------------------------|
| `b` | `byte`: the buffer into which the data is read
|
| Returns ||
|-------|-----------------------------------------------------------------------------------------------|
| `int` | the actual number of bytes read, -1 is returned when the end of the stream is reached.
|
| Throws ||
|----------------------------------------------------------------------------|-------------------------------|
| [IOException](https://developer.android.com/reference/java/io/IOException) | If an I/O error has occurred. |
### readObject
Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public abstract Object readObject ()
```
Read and return an object. The class that implements this interface defines where the object is "read" from.
| Returns ||
|--------------------------------------------------------------------|----------------------------------------|
| [Object](https://developer.android.com/reference/java/lang/Object) | the object read from the stream
|
| Throws ||
|----------------------------------------------------------------------------------------------------|------------------------------------------------------------|
| [ClassNotFoundException](https://developer.android.com/reference/java/lang/ClassNotFoundException) | If the class of a serialized object cannot be found. |
| [IOException](https://developer.android.com/reference/java/io/IOException) | If any of the usual Input/Output related exceptions occur. |
### skip
Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)
```
public abstract long skip (long n)
```
Skips n bytes of input.
| Parameters ||
|-----|--------------------------------------------------|
| `n` | `long`: the number of bytes to be skipped
|
| Returns ||
|--------|--------------------------------------------|
| `long` | the actual number of bytes skipped.
|
| Throws ||
|----------------------------------------------------------------------------|-------------------------------|
| [IOException](https://developer.android.com/reference/java/io/IOException) | If an I/O error has occurred. |