TemplateBuilderChain.java

//
// MessagePack for Java
//
// Copyright (C) 2009-2011 FURUHASHI Sadayuki
//
//    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
//
//        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.msgpack.template.builder;

import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.List;

import org.msgpack.template.TemplateRegistry;


public class TemplateBuilderChain {

    private static boolean enableDynamicCodeGeneration(){
	try {
	    return !System.getProperty("java.vm.name").equals("Dalvik");
	} catch (Exception e) {
	    return true;
	}
    }

    protected List<TemplateBuilder> templateBuilders;

    protected TemplateBuilder forceBuilder;

    public TemplateBuilderChain(final TemplateRegistry registry) {
	this(registry, null);
    }

    public TemplateBuilderChain(final TemplateRegistry registry, final ClassLoader cl) {
	templateBuilders = new ArrayList<TemplateBuilder>();
	reset(registry, cl);
    }

    protected void reset(final TemplateRegistry registry, final ClassLoader cl) {
	if (registry == null) {
	    throw new NullPointerException("registry is null");
	}

	// forceBuilder
	forceBuilder = new JavassistTemplateBuilder(registry);
	if (cl != null) {
	    ((JavassistTemplateBuilder) forceBuilder).addClassLoader(cl);
	}

	// builder
	TemplateBuilder builder;
	templateBuilders.add(new ArrayTemplateBuilder(registry));
	templateBuilders.add(new OrdinalEnumTemplateBuilder(registry));
	if (enableDynamicCodeGeneration()) { // use dynamic code generation
	    builder = forceBuilder;
	    templateBuilders.add(builder);
	    // FIXME #MN next version
	    //templateBuilders.add(new JavassistBeansTemplateBuilder(registry));
	    templateBuilders.add(new ReflectionBeansTemplateBuilder(registry));
	} else { // use reflection
	    builder = new ReflectionTemplateBuilder(registry);
	    templateBuilders.add(builder);
	    templateBuilders.add(new ReflectionBeansTemplateBuilder(registry));
	}
    }

    public TemplateBuilder getForceBuilder() {
	return forceBuilder;
    }

    public TemplateBuilder select(final Type targetType, final boolean hasAnnotation) {
	for (TemplateBuilder tb : templateBuilders) {
	    if (tb.matchType(targetType, hasAnnotation)) {
		return tb;
	    }
	}
	return null;
    }
}