java.io
Class CharArrayReaderjava.lang.Object | +--java.io.Reader | +--java.io.CharArrayReader
- public class CharArrayReader
- extends Reader
This class implements a character buffer that can be used as a character-input stream.
- Since:
- JDK1.1
Field Summary
protected char[] buf
The character buffer.protected int count
The index of the end of this buffer.protected int markedPos
The position of mark in buffer.protected int pos
The current buffer position.
Fields inherited from class java.io.Reader lock
Constructor Summary
CharArrayReader(char[] buf)
Create an CharArrayReader from the specified array of chars.CharArrayReader(char[] buf, int offset, int length)
Create an CharArrayReader from the specified array of chars.
Method Summary
void close()
Close the stream.void mark(int readAheadLimit)
Mark the present position in the stream.boolean markSupported()
Tell whether this stream supports the mark() operation, which it does.int read()
Read a single character.int read(char[] b, int off, int len)
Read characters into a portion of an array.boolean ready()
Tell whether this stream is ready to be read.void reset()
Reset the stream to the most recent mark, or to the beginning if it has never been marked.long skip(long n)
Skip characters.
Methods inherited from class java.io.Reader read
Methods inherited from class java.lang.Object clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Field Detail
buf
protected char[] buf
- The character buffer.
pos
protected int pos
- The current buffer position.
markedPos
protected int markedPos
- The position of mark in buffer.
count
protected int count
- The index of the end of this buffer. There is not valid data at or beyond this index.
Constructor Detail
CharArrayReader
public CharArrayReader(char[] buf)
- Create an CharArrayReader from the specified array of chars.
- Parameters:
- buf - Input buffer (not copied)
CharArrayReader
public CharArrayReader(char[] buf, int offset, int length)
- Create an CharArrayReader from the specified array of chars.
- Parameters:
- buf - Input buffer (not copied)
- offset - Offset of the first char to read
- length - Number of chars to read
Method Detail
read
public int read() throws IOException
- Read a single character.
- Overrides:
- read in class Reader
- Returns:
- 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:
- IOException - If an I/O error occurs
read
public int read(char[] b, int off, int len) throws IOException
- Read characters into a portion of an array.
- Specified by:
- read in class Reader
- Parameters:
- b - Destination buffer
- off - Offset at which to start storing characters
- len - Maximum number of characters to read
- Returns:
- The actual number of characters read, or -1 if the end of the stream has been reached
- Throws:
- IOException - If an I/O error occurs
skip
public long skip(long n) throws IOException
- Skip characters.
- Overrides:
- skip in class Reader
- Parameters:
- n - The number of characters to skip
- Returns:
- The number of characters actually skipped
- Throws:
- IOException - If an I/O error occurs
ready
public boolean ready() throws IOException
- Tell whether this stream is ready to be read. Character-array readers are always ready to be read.
- Overrides:
- ready in class Reader
- Returns:
- 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:
- IOException - If an I/O error occurs
markSupported
public boolean markSupported()
- Tell whether this stream supports the mark() operation, which it does.
- Overrides:
- markSupported in class Reader
- Returns:
- true if and only if this stream supports the mark operation.
mark
public void mark(int readAheadLimit) throws IOException
- Mark the present position in the stream. Subsequent calls to reset() will reposition the stream to this point.
- Overrides:
- mark in class Reader
- Parameters:
- readAheadLimit - Limit on the number of characters that may be read while still preserving the mark. Because the stream's input comes from a character array, there is no actual limit; hence this argument is ignored.
- Throws:
- IOException - If an I/O error occurs
reset
public void reset() throws IOException
- Reset the stream to the most recent mark, or to the beginning if it has never been marked.
- Overrides:
- reset in class Reader
- Throws:
- IOException - If an I/O error occurs
close
public void close()
- Close the stream.
- Specified by:
- close in class Reader