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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package sun.io;
import java.io.*;
/**
* An abstract base class for subclasses which convert character data
* in an external encoding into Unicode characters.
*
* @author Asmus Freytag
* @author Lloyd Honomichl
*
* @deprecated Replaced by {@link java.nio.charset}. THIS API WILL BE
* REMOVED IN J2SE 1.6.
*/
@Deprecated
public abstract class ByteToCharConverter {
/*
* Substitution mode flag.
*/
protected boolean subMode = true;
/*
* Characters to use for automatic substitution.
*/
protected char[] subChars = { '\uFFFD' };
/*
* Offset of next character to be output
*/
protected int charOff;
/*
* Offset of next byte to be converted
*/
protected int byteOff;
/*
* Length of bad input that caused a MalformedInputException.
*/
protected int badInputLength;
/**
* Create an instance of the default ByteToCharConverter subclass.
*/
public static ByteToCharConverter getDefault() {
Object cvt;
cvt = Converters.newDefaultConverter(Converters.BYTE_TO_CHAR);
return (ByteToCharConverter)cvt;
}
/**
* Returns appropriate ByteToCharConverter subclass instance.
* @param string represents encoding
*/
public static ByteToCharConverter getConverter(String encoding)
throws UnsupportedEncodingException
{
Object cvt;
cvt = Converters.newConverter(Converters.BYTE_TO_CHAR, encoding);
return (ByteToCharConverter)cvt;
}
/**
* Returns the character set id for the conversion
*/
public abstract String getCharacterEncoding();
/**
* Converts an array of bytes containing characters in an external
* encoding into an array of Unicode characters. This method allows
* a buffer by buffer conversion of a data stream. The state of the
* conversion is saved between calls to convert. Among other things,
* this means multibyte input sequences can be split between calls.
* If a call to convert results in an exception, the conversion may be
* continued by calling convert again with suitably modified parameters.
* All conversions should be finished with a call to the flush method.
*
* @return the number of bytes written to output.
* @param input byte array containing text to be converted.
* @param inStart begin conversion at this offset in input array.
* @param inEnd stop conversion at this offset in input array (exclusive).
* @param output character array to receive conversion result.
* @param outStart start writing to output array at this offset.
* @param outEnd stop writing to output array at this offset (exclusive).
* @exception MalformedInputException if the input buffer contains any
* sequence of bytes that is illegal for the input character set.
* @exception UnknownCharacterException for any character that
* that cannot be converted to Unicode. Thrown only when converter
* is not in substitution mode.
* @exception ConversionBufferFullException if output array is filled prior
* to converting all the input.
*/
public abstract int convert(byte[] input, int inStart, int inEnd,
char[] output, int outStart, int outEnd)
throws MalformedInputException,
UnknownCharacterException,
ConversionBufferFullException;
/**
* Converts an array of bytes containing characters in an external
* encoding into an array of Unicode characters. Unlike convert,
* this method does not do incremental conversion. It assumes that
* the given input array contains all the characters to be
* converted. The state of the converter is reset at the beginning
* of this method and is left in the reset state on successful
* termination. The converter is not reset if an exception is
* thrown. This allows the caller to determine where the bad input
* was encountered by calling nextByteIndex.
* <p>
* This method uses substitution mode when performing the
* conversion. The method setSubstitutionChars may be used to
* determine what characters are substituted. Even though substitution
* mode is used, the state of the converter's substitution mode is
* not changed at the end of this method.
*
* @return an array of chars containing the converted characters.
* @param input array containing Unicode characters to be converted.
* @exception MalformedInputException if the input buffer contains any
* sequence of chars that is illegal in the input character encoding.
* After this exception is thrown,
* the method nextByteIndex can be called to obtain the index of the
* first invalid input byte and getBadInputLength can be called
* to determine the length of the invalid input.
*
* @see #nextByteIndex
* @see #setSubstitutionMode
* @see sun.io.CharToByteConverter#setSubstitutionBytes(byte[])
* @see #getBadInputLength
*/
public char[] convertAll( byte input[] ) throws MalformedInputException {
reset();
boolean savedSubMode = subMode;
subMode = true;
char[] output = new char[ getMaxCharsPerByte() * input.length ];
try {
int outputLength = convert( input, 0, input.length,
output, 0, output.length );
outputLength += flush( output, outputLength, output.length );
char [] returnedOutput = new char[ outputLength ];
System.arraycopy( output, 0, returnedOutput, 0, outputLength );
return returnedOutput;
}
catch( ConversionBufferFullException e ) {
//Not supposed to happen. If it does, getMaxCharsPerByte() lied.
throw new
InternalError("this.getMaxCharsBerByte returned bad value");
}
catch( UnknownCharacterException e ) {
// Not supposed to happen since we're in substitution mode.
throw new InternalError();
}
finally {
subMode = savedSubMode;
}
}
/**
* Writes any remaining output to the output buffer and resets the
* converter to its initial state.
*
* @param output char array to receive flushed output.
* @param outStart start writing to output array at this offset.
* @param outEnd stop writing to output array at this offset (exclusive).
* @exception MalformedInputException if the output to be flushed contained
* a partial or invalid multibyte character sequence. flush will
* write what it can to the output buffer and reset the converter before
* throwing this exception. An additional call to flush is not required.
* @exception ConversionBufferFullException if output array is filled
* before all the output can be flushed. flush will write what it can
* to the output buffer and remember its state. An additional call to
* flush with a new output buffer will conclude the operation.
*/
public abstract int flush( char[] output, int outStart, int outEnd )
throws MalformedInputException, ConversionBufferFullException;
/**
* Resets converter to its initial state.
*/
public abstract void reset();
/**
* Returns the maximum number of characters needed to convert a byte. Useful
* for calculating the maximum output buffer size needed for a particular
* input buffer.
*/
public int getMaxCharsPerByte() {
// Until UTF-16, this will do for every encoding
return 1;
}
/**
* Returns the length, in bytes, of the input which caused a
* MalformedInputException. Always refers to the last
* MalformedInputException thrown by the converter. If none have
* ever been thrown, returns 0.
*/
public int getBadInputLength() {
return badInputLength;
}
/**
* Returns the index of the character just past the last character
* written by the previous call to convert.
*/
public int nextCharIndex() {
return charOff;
}
/**
* Returns the index of the byte just past the last byte successfully
* converted by the previous call to convert.
*/
public int nextByteIndex() {
return byteOff;
}
/**
* Sets converter into substitution mode. In substitution mode,
* the converter will replace untranslatable characters in the source
* encoding with the substitution character set by setSubstitionChars.
* When not in substitution mode, the converter will throw an
* UnknownCharacterException when it encounters untranslatable input.
*
* @param doSub if true, enable substitution mode.
* @see #setSubstitutionChars
*/
public void setSubstitutionMode(boolean doSub) {
subMode = doSub;
}
/**
* Sets the substitution characters to use when the converter is in
* substitution mode. The given chars must not be
* longer than the value returned by getMaxCharsPerByte for this
* converter.
*
* @param newSubBytes the substitution bytes
* @exception IllegalArgumentException if given byte array is longer than
* the value returned by the method getMaxBytesPerChar.
* @see #setSubstitutionMode
* @see #getMaxBytesPerChar
*/
/**
* sets the substitution character to use
* @param c the substitution character
*/
public void setSubstitutionChars(char[] c)
throws IllegalArgumentException
{
if( c.length > getMaxCharsPerByte() ) {
throw new IllegalArgumentException();
}
subChars = new char[ c.length ];
System.arraycopy( c, 0, subChars, 0, c.length );
}
/**
* returns a string representation of the character conversion
*/
public String toString() {
return "ByteToCharConverter: " + getCharacterEncoding();
}
}