package org.apache.cassandra.db.marshal;
/*
*
* 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.
*
*/
import java.nio.ByteBuffer;
import java.sql.Types;
import org.apache.cassandra.utils.ByteBufferUtil;
public class DoubleType extends AbstractType<Double>
{
public static final DoubleType instance = new DoubleType();
DoubleType() {} // singleton
public Double compose(ByteBuffer bytes)
{
return ByteBufferUtil.toDouble(bytes);
}
public ByteBuffer decompose(Double value)
{
return (value==null) ? ByteBufferUtil.EMPTY_BYTE_BUFFER : ByteBufferUtil.bytes(value);
}
public int compare(ByteBuffer o1, ByteBuffer o2)
{
if (o1.remaining() == 0)
{
return o2.remaining() == 0 ? 0 : -1;
}
if (o2.remaining() == 0)
{
return 1;
}
return compose(o1).compareTo(compose(o2));
}
public String getString(ByteBuffer bytes)
{
if (bytes.remaining() == 0)
{
return "";
}
if (bytes.remaining() != 8)
{
throw new MarshalException("A double is exactly 8 bytes : "+bytes.remaining());
}
return compose(bytes).toString();
}
public String toString(Double d)
{
return d.toString();
}
public ByteBuffer fromString(String source) throws MarshalException
{
// Return an empty ByteBuffer for an empty string.
if (source.isEmpty())
return ByteBufferUtil.EMPTY_BYTE_BUFFER;
Double d;
try
{
d = Double.parseDouble(source);
}
catch (NumberFormatException e1)
{
throw new MarshalException(String.format("unable to coerce '%s' to a double", source), e1);
}
return decompose(d);
}
public void validate(ByteBuffer bytes) throws MarshalException
{
if (bytes.remaining() != 8 && bytes.remaining() != 0)
throw new MarshalException(String.format("Expected 8 or 0 byte value for a double (%d)", bytes.remaining()));
}
public Class<Double> getType()
{
return Double.class;
}
public boolean isSigned()
{
return true;
}
public boolean isCaseSensitive()
{
return false;
}
public boolean isCurrency()
{
return false;
}
public int getPrecision(Double obj) // see: http://teaching.idallen.org/dat2343/09f/notes/10FloatingPoint.htm
{
return 15;
}
public int getScale(Double obj) // see: http://teaching.idallen.org/dat2343/09f/notes/10FloatingPoint.htm
{
return 300;
}
public int getJdbcType()
{
return Types.DOUBLE;
}
public boolean needsQuotes()
{
return false;
}
}