org.apache.qpid.proton.codec.StringType Maven / Gradle / Ivy
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*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
package org.apache.qpid.proton.codec;
import java.nio.charset.CharacterCodingException;
import java.nio.charset.CharsetDecoder;
import java.util.Arrays;
import java.util.Collection;
public class StringType extends AbstractPrimitiveType
{
private static final DecoderImpl.TypeDecoder _stringCreator =
new DecoderImpl.TypeDecoder()
{
@Override
public String decode(DecoderImpl decoder, final ReadableBuffer buffer)
{
CharsetDecoder charsetDecoder = decoder.getCharsetDecoder();
try
{
return buffer.readString(charsetDecoder);
}
catch (CharacterCodingException e)
{
throw new IllegalArgumentException("Cannot parse String");
}
finally
{
charsetDecoder.reset();
}
}
};
public static interface StringEncoding extends PrimitiveTypeEncoding
{
void setValue(String val, int length);
}
private final StringEncoding _stringEncoding;
private final StringEncoding _shortStringEncoding;
StringType(final EncoderImpl encoder, final DecoderImpl decoder)
{
_stringEncoding = new AllStringEncoding(encoder, decoder);
_shortStringEncoding = new ShortStringEncoding(encoder, decoder);
encoder.register(String.class, this);
decoder.register(this);
}
@Override
public Class getTypeClass()
{
return String.class;
}
@Override
public StringEncoding getEncoding(final String val)
{
final int length = calculateUTF8Length(val);
StringEncoding encoding = length <= 255
? _shortStringEncoding
: _stringEncoding;
encoding.setValue(val, length);
return encoding;
}
static int calculateUTF8Length(final String s)
{
final int stringLength = s.length();
// ASCII Optimized length case
int utf8len = stringLength;
int processed = 0;
for (; processed < stringLength && s.charAt(processed) < 0x80; processed++) {}
if (processed < stringLength)
{
// Non-ASCII length remainder
utf8len = extendedCalculateUTF8Length(s, processed, stringLength, utf8len);
}
return utf8len;
}
static int extendedCalculateUTF8Length(final String s, int index, int length, int utf8len) {
for (; index < length; index++)
{
int c = s.charAt(index);
if ((c & 0xFF80) != 0) /* U+0080.. */
{
utf8len++;
if(((c & 0xF800) != 0)) /* U+0800.. */
{
utf8len++;
// surrogate pairs should always combine to create a code point with a 4 octet representation
if ((c & 0xD800) == 0xD800 && c < 0xDC00)
{
index++;
}
}
}
}
return utf8len;
}
@Override
public StringEncoding getCanonicalEncoding()
{
return _stringEncoding;
}
@Override
public Collection getAllEncodings()
{
return Arrays.asList(_shortStringEncoding, _stringEncoding);
}
private class AllStringEncoding
extends LargeFloatingSizePrimitiveTypeEncoding
implements StringEncoding
{
private String _value;
private int _length;
public AllStringEncoding(final EncoderImpl encoder, final DecoderImpl decoder)
{
super(encoder, decoder);
}
@Override
protected void writeEncodedValue(final String val)
{
getEncoder().getBuffer().ensureRemaining(getEncodedValueSize(val));
getEncoder().writeRaw(val);
}
@Override
protected int getEncodedValueSize(final String val)
{
return (val == _value) ? _length : calculateUTF8Length(val);
}
@Override
public byte getEncodingCode()
{
return EncodingCodes.STR32;
}
@Override
public StringType getType()
{
return StringType.this;
}
@Override
public boolean encodesSuperset(final TypeEncoding encoding)
{
return (getType() == encoding.getType());
}
@Override
public String readValue()
{
DecoderImpl decoder = getDecoder();
int size = decoder.readRawInt();
return size == 0 ? "" : decoder.readRaw(_stringCreator, size);
}
@Override
public void setValue(final String val, final int length)
{
_value = val;
_length = length;
}
@Override
public void skipValue()
{
DecoderImpl decoder = getDecoder();
ReadableBuffer buffer = decoder.getBuffer();
int size = decoder.readRawInt();
buffer.position(buffer.position() + size);
}
}
private class ShortStringEncoding
extends SmallFloatingSizePrimitiveTypeEncoding
implements StringEncoding
{
private String _value;
private int _length;
public ShortStringEncoding(final EncoderImpl encoder, final DecoderImpl decoder)
{
super(encoder, decoder);
}
@Override
protected void writeEncodedValue(final String val)
{
getEncoder().getBuffer().ensureRemaining(getEncodedValueSize(val));
getEncoder().writeRaw(val);
}
@Override
protected int getEncodedValueSize(final String val)
{
return (val == _value) ? _length : calculateUTF8Length(val);
}
@Override
public byte getEncodingCode()
{
return EncodingCodes.STR8;
}
@Override
public StringType getType()
{
return StringType.this;
}
@Override
public boolean encodesSuperset(final TypeEncoding encoder)
{
return encoder == this;
}
@Override
public String readValue()
{
DecoderImpl decoder = getDecoder();
int size = ((int)decoder.readRawByte()) & 0xff;
return size == 0 ? "" : decoder.readRaw(_stringCreator, size);
}
@Override
public void setValue(final String val, final int length)
{
_value = val;
_length = length;
}
@Override
public void skipValue()
{
DecoderImpl decoder = getDecoder();
ReadableBuffer buffer = decoder.getBuffer();
int size = ((int)decoder.readRawByte()) & 0xff;
buffer.position(buffer.position() + size);
}
}
}