org.springframework.integration.codec.CompositeCodec Maven / Gradle / Ivy
/*
* Copyright 2015-2019 the original author or authors.
*
* Licensed 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
*
* https://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.springframework.integration.codec;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Map;
import org.springframework.integration.util.ClassUtils;
import org.springframework.util.Assert;
/**
* A Codec that can delegate to one out of many Codecs, each mapped to a class.
* @author David Turanski
* @since 4.2
*/
public class CompositeCodec implements Codec {
private final Codec defaultCodec;
private final Map, Codec> delegates;
public CompositeCodec(Map, Codec> delegates, Codec defaultCodec) {
Assert.notNull(defaultCodec, "'defaultCodec' cannot be null");
this.defaultCodec = defaultCodec;
this.delegates = new HashMap, Codec>(delegates);
}
public CompositeCodec(Codec defaultCodec) {
this(null, defaultCodec);
}
@Override
public void encode(Object object, OutputStream outputStream) throws IOException {
Assert.notNull(object, "cannot encode a null object");
Assert.notNull(outputStream, "'outputStream' cannot be null");
Codec codec = findDelegate(object.getClass());
if (codec != null) {
codec.encode(object, outputStream);
}
else {
this.defaultCodec.encode(object, outputStream);
}
}
@Override
public byte[] encode(Object object) throws IOException {
Assert.notNull(object, "cannot encode a null object");
Codec codec = findDelegate(object.getClass());
if (codec != null) {
return codec.encode(object);
}
else {
return this.defaultCodec.encode(object);
}
}
@Override
public T decode(InputStream inputStream, Class type) throws IOException {
Assert.notNull(inputStream, "'inputStream' cannot be null");
Assert.notNull(type, "'type' cannot be null");
Codec codec = findDelegate(type);
if (codec != null) {
return codec.decode(inputStream, type);
}
else {
return this.defaultCodec.decode(inputStream, type);
}
}
@Override
public T decode(byte[] bytes, Class type) throws IOException {
return decode(new ByteArrayInputStream(bytes), type);
}
private Codec findDelegate(Class type) {
if (this.delegates == null) {
return null;
}
Class clazz = ClassUtils.findClosestMatch(type, this.delegates.keySet(), false);
return this.delegates.get(clazz);
}
}