com.codename1.io

Class CharArrayReader

java.lang.Object

java.io.Reader

com.codename1.io.CharArrayReader

All Implemented Interfaces:

Closeable, AutoCloseable, Readable

public class CharArrayReader
extends Reader

A specialized Reader for reading the contents of a char array.

See Also:

CharArrayWriter

Field Summary

Fields

Modifier and Type	Field and Description
protected char[]	buf The buffer for characters.
protected int	count The ending index of the buffer.
protected int	markedPos The current mark position.
protected int	pos The current buffer position.

Fields inherited from class java.io.Reader

lock

Constructor Summary

Constructors

Constructor and Description
CharArrayReader(char[] buf) Constructs a CharArrayReader on the char array buf.
CharArrayReader(char[] buf, int offset, int length) Constructs a CharArrayReader on the char array buf.

Method Summary

Modifier and Type	Method and Description
void	close() This method closes this CharArrayReader.
void	mark(int readLimit) Sets a mark position in this reader.
boolean	markSupported() Indicates whether this reader supports the mark() and reset() methods.
int	read() Reads a single character from this reader and returns it as an integer with the two higher-order bytes set to 0.
int	read(char[] buffer, int offset, int len) Reads at most count characters from this CharArrayReader and stores them at offset in the character array buf.
boolean	ready() Indicates whether this reader is ready to be read without blocking.
void	reset() Resets this reader's position to the last mark() location.
long	skip(long n) Skips count number of characters in this reader.

Methods inherited from class java.io.Reader

read, 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 buffer for characters.

pos

protected int pos

The current buffer position.

markedPos

protected int markedPos

The current mark position.

count

protected int count

The ending index of the buffer.

Constructor Detail

CharArrayReader

public CharArrayReader(char[] buf)

Constructs a CharArrayReader on the char array buf. The size of the reader is set to the length of the buffer and the object to read from is set to buf.

Parameters:

buf - the char array from which to read.

CharArrayReader

public CharArrayReader(char[] buf,
                       int offset,
                       int length)

Constructs a CharArrayReader on the char array buf. The size of the reader is set to length and the start position from which to read the buffer is set to offset.

Parameters:

buf - the char array from which to read.

offset - the index of the first character in buf to read.

length - the number of characters that can be read from buf.

Throws:

IllegalArgumentException - if offset < 0 or length < 0, or if offset is greater than the size of buf .

Method Detail

close

public void close()

This method closes this CharArrayReader. Once it is closed, you can no longer read from it. Only the first invocation of this method has any effect.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Specified by:

close in class Reader

mark

public void mark(int readLimit)
          throws IOException

Sets a mark position in this reader. The parameter readLimit is ignored for CharArrayReaders. Calling reset() will reposition the reader back to the marked position provided the mark has not been invalidated.

Overrides:

mark in class Reader

Parameters:

readLimit - ignored for CharArrayReaders.

Throws:

IOException - if this reader is closed.

markSupported

public boolean markSupported()

Indicates whether this reader supports the mark() and reset() methods.

Overrides:

markSupported in class Reader

Returns:

true for CharArrayReader.

See Also:

mark(int), reset()

read

public int read()
         throws IOException

Reads a single character from this reader and returns it as an integer with the two higher-order bytes set to 0. Returns -1 if no more characters are available from this reader.

Overrides:

read in class Reader

Returns:

the character read as an int or -1 if the end of the reader has been reached.

Throws:

IOException - if this reader is closed.

read

public int read(char[] buffer,
                int offset,
                int len)
         throws IOException

Reads at most count characters from this CharArrayReader and stores them at offset in the character array buf. Returns the number of characters actually read or -1 if the end of reader was encountered.

Specified by:

read in class Reader

Parameters:

buffer - the character array to store the characters read.

offset - the initial position in buffer to store the characters read from this reader.

len - the maximum number of characters to read.

Returns:

number of characters read or -1 if the end of the reader has been reached.

Throws:

IndexOutOfBoundsException - if offset < 0 or len < 0, or if offset + len is bigger than the size of buffer.

IOException - if this reader is closed.

ready

public boolean ready()
              throws IOException

Indicates whether this reader is ready to be read without blocking. Returns true if the next read will not block. Returns false if this reader may or may not block when read is called. The implementation in CharArrayReader always returns true even when it has been closed.

Overrides:

ready in class Reader

Returns:

true if this reader will not block when read is called, false if unknown or blocking will occur.

Throws:

IOException - if this reader is closed.

reset

public void reset()
           throws IOException

Resets this reader's position to the last mark() location. Invocations of read() and skip() will occur from this new location. If this reader has not been marked, it is reset to the beginning of the string.

Overrides:

reset in class Reader

Throws:

IOException - if this reader is closed.

skip

public long skip(long n)
          throws IOException

Skips count number of characters in this reader. Subsequent read()s will not return these characters unless reset() is used. This method does nothing and returns 0 if n is negative.

Overrides:

skip in class Reader

Parameters:

n - the number of characters to skip.

Returns:

the number of characters actually skipped.

Throws:

IOException - if this reader is closed.