程序包 java.io

类 StringReader

java.lang.Object

java.io.Reader

java.io.StringReader

所有已实现的接口:

Closeable, AutoCloseable, Readable

public class StringReader
extends Reader

A character stream whose source is a string.

从以下版本开始:

JDK1.1

字段概要

从类继承的字段 java.io.Reader

lock

构造器概要

构造器

构造器	说明
StringReader(String s)	Creates a new string reader.

方法概要

限定符和类型	方法	说明
void	close()	Closes the stream and releases any system resources associated with it.
void	mark(int readAheadLimit)	Marks the present position in the stream.
boolean	markSupported()	Tells whether this stream supports the mark() operation, which it does.
int	read()	Reads a single character.
int	read(char[] cbuf, int off, int len)	Reads characters into a portion of an array.
boolean	ready()	Tells whether this stream is ready to be read.
void	reset()	Resets the stream to the most recent mark, or to the beginning of the string if it has never been marked.
long	skip(long ns)	Skips the specified number of characters in the stream.

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

从类继承的方法 java.io.Reader

read, read

构造器详细资料

StringReader

public StringReader(String s)

Creates a new string reader.

参数:

s - String providing the character stream.

方法详细资料

read

public int read()
         throws IOException

Reads a single character.

覆盖:

read 在类中 Reader

返回:

The character read, or -1 if the end of the stream has been reached

抛出:

IOException - If an I/O error occurs

read

public int read(char[] cbuf,
                int off,
                int len)
         throws IOException

Reads characters into a portion of an array.

指定者:

read 在类中 Reader

参数:

cbuf - Destination buffer

off - Offset at which to start writing characters

len - Maximum number of characters to read

返回:

The number of characters read, or -1 if the end of the stream has been reached

抛出:

IOException - If an I/O error occurs

skip

public long skip(long ns)
          throws IOException

Skips the specified number of characters in the stream. Returns the number of characters that were skipped.

The ns parameter may be negative, even though the skip method of the Reader superclass throws an exception in this case. Negative values of ns cause the stream to skip backwards. Negative return values indicate a skip backwards. It is not possible to skip backwards past the beginning of the string.

If the entire string has been read or skipped, then this method has no effect and always returns 0.

覆盖:

skip 在类中 Reader

参数:

ns - The number of characters to skip

返回:

The number of characters actually skipped

抛出:

IOException - If an I/O error occurs

ready

public boolean ready()
              throws IOException

Tells whether this stream is ready to be read.

覆盖:

ready 在类中 Reader

返回:

True if the next read() is guaranteed not to block for input

抛出:

IOException - If the stream is closed

markSupported

public boolean markSupported()

Tells whether this stream supports the mark() operation, which it does.

覆盖:

markSupported 在类中 Reader

返回:

true if and only if this stream supports the mark operation.

mark

public void mark(int readAheadLimit)
          throws IOException

Marks the present position in the stream. Subsequent calls to reset() will reposition the stream to this point.

覆盖:

mark 在类中 Reader

参数:

readAheadLimit - Limit on the number of characters that may be read while still preserving the mark. Because the stream's input comes from a string, there is no actual limit, so this argument must not be negative, but is otherwise ignored.

抛出:

IllegalArgumentException - If readAheadLimit < 0

IOException - If an I/O error occurs

reset

public void reset()
           throws IOException

Resets the stream to the most recent mark, or to the beginning of the string if it has never been marked.

覆盖:

reset 在类中 Reader

抛出:

IOException - If an I/O error occurs

close

public void close()

Closes the stream and releases any system resources associated with it. Once the stream has been closed, further read(), ready(), mark(), or reset() invocations will throw an IOException. Closing a previously closed stream has no effect.

指定者:

close 在接口中 AutoCloseable

指定者:

close 在接口中 Closeable

指定者:

close 在类中 Reader