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InputStream.Read Method

Definition

Overloads

Read()

Reads the next byte of data from the input stream.

Read(Byte[])

Reads some number of bytes from the input stream and stores them into the buffer array b.

Read(Byte[], Int32, Int32)

Reads up to len bytes of data from the input stream into an array of bytes.

Read()

Reads the next byte of data from the input stream.

[Android.Runtime.Register("read", "()I", "GetReadHandler")]
public abstract int Read ();
[<Android.Runtime.Register("read", "()I", "GetReadHandler")>]
abstract member Read : unit -> int

Returns

the next byte of data, or -1 if the end of the stream is reached.

Attributes

Exceptions

if the stream is closed or another IOException occurs.

Remarks

Reads the next byte of data from the 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 method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

A subclass must provide an implementation of this method.

Java documentation for java.io.InputStream.read().

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to

Read(Byte[])

Reads some number of bytes from the input stream and stores them into the buffer array b.

[Android.Runtime.Register("read", "([B)I", "GetRead_arrayBHandler")]
public virtual int Read (byte[]? b);
[<Android.Runtime.Register("read", "([B)I", "GetRead_arrayBHandler")>]
abstract member Read : byte[] -> int
override this.Read : byte[] -> int

Parameters

b
Byte[]

the buffer into which the data is read.

Returns

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.

Attributes

Exceptions

Remarks

Reads some number of bytes from the input stream and stores them into the buffer array b. The number of bytes actually read is returned as an integer. This method blocks until input data is available, end of file is detected, or an exception is thrown.

If the length of b is zero, then no bytes are read and 0 is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at the end of the file, the value -1 is returned; otherwise, at least one byte is read and stored into b.

The first byte read is stored into element b[0], the next one into b[1], and so on. The number of bytes read is, at most, equal to the length of b. Let k be the number of bytes actually read; these bytes will be stored in elements b[0] through b[k-1], leaving elements b[k] through b[b.length-1] unaffected.

The read(b) method for class InputStream has the same effect as:

{@code read(b, 0, b.length) }

Java documentation for java.io.InputStream.read(byte[]).

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to

Read(Byte[], Int32, Int32)

Reads up to len bytes of data from the input stream into an array of bytes.

[Android.Runtime.Register("read", "([BII)I", "GetRead_arrayBIIHandler")]
public virtual int Read (byte[]? b, int off, int len);
[<Android.Runtime.Register("read", "([BII)I", "GetRead_arrayBIIHandler")>]
abstract member Read : byte[] * int * int -> int
override this.Read : byte[] * int * int -> int

Parameters

b
Byte[]

the buffer into which the data is read.

off
Int32

the start offset in array b at which the data is written.

len
Int32

the maximum number of bytes to read.

Returns

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.

Attributes

Exceptions

if byteOffset buffer.length.

if the stream is closed or another IOException occurs.

Remarks

Reads up to len bytes of data from the input stream into an array of bytes. An attempt is made to read as many as len bytes, but a smaller number may be read. The number of bytes actually read is returned as an integer.

This method blocks until input data is available, end of file is detected, or an exception is thrown.

If len is zero, then no bytes are read and 0 is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at end of file, the value -1 is returned; otherwise, at least one byte is read and stored into b.

The first byte read is stored into element b[off], the next one into 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.

In every case, elements b[0] through b[off-1] and elements b[off+len] through b[b.length-1] are unaffected.

The read(b, off, len) method for class InputStream simply calls the method read() repeatedly. If the first such call results in an IOException, that exception is returned from the call to the read(b,off,len) method. If any subsequent call to read() results in a IOException, the exception is caught and treated as if it were end of file; the bytes read up to that point are stored into b and the number of bytes read before the exception occurred is returned. The default implementation of this method blocks until the requested amount of input data len has been read, end of file is detected, or an exception is thrown. Subclasses are encouraged to provide a more efficient implementation of this method.

Java documentation for java.io.InputStream.read(byte[], int, int).

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to