package com.firefly.utils.classproxy;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.ConcurrentHashMap;
import javassist.ClassClassPath;
import javassist.ClassPool;
import javassist.CtClass;
import javassist.CtMethod;
import com.firefly.utils.ReflectUtils.ArrayProxy;
import com.firefly.utils.StringUtils;
public class ArrayProxyFactoryUsingJavassist extends AbstractArrayProxyFactory {
private static final Map<Class<?>, ArrayProxy> arrayCache = new ConcurrentHashMap<Class<?>, ArrayProxy>();
public static final ArrayProxyFactoryUsingJavassist INSTANCE = new ArrayProxyFactoryUsingJavassist();
private ArrayProxyFactoryUsingJavassist() {
}
@Override
public ArrayProxy getArrayProxy(Class<?> clazz) throws Throwable {
if(!clazz.isArray())
throw new IllegalArgumentException("type error, it's not array");
ArrayProxy ret = arrayCache.get(clazz);
if(ret != null)
return ret;
synchronized(arrayCache) {
ret = arrayCache.get(clazz);
if(ret != null)
return ret;
ret = _getArrayProxy(clazz);
arrayCache.put(clazz, ret);
return ret;
}
}
@SuppressWarnings("unchecked")
private ArrayProxy _getArrayProxy(Class<?> clazz) throws Throwable {
// long start = System.currentTimeMillis();
ClassPool classPool = ClassPool.getDefault();
classPool.insertClassPath(new ClassClassPath(ArrayProxy.class));
CtClass cc = classPool.makeClass("com.firefly.utils.ArrayField" + UUID.randomUUID().toString().replace("-", ""));
cc.addInterface(classPool.get(ArrayProxy.class.getName()));
cc.addMethod(CtMethod.make(createArraySizeCode(clazz), cc));
cc.addMethod(CtMethod.make(createArrayGetCode(clazz), cc));
cc.addMethod(CtMethod.make(createArraySetCode(clazz), cc));
ArrayProxy ret = (ArrayProxy) cc.toClass().getConstructor().newInstance();
// long end = System.currentTimeMillis();
// System.out.println("Javassist generates class proxy time -> " + (end - start));
return ret;
}
private String createArraySetCode(Class<?> clazz) {
StringBuilder code = new StringBuilder();
code.append("public void set(Object array, int index, Object value){\n")
.append(StringUtils.replace("\t(({})array)[index] = ", clazz.getCanonicalName()));
Class<?> componentType = clazz.getComponentType();
if(componentType.isPrimitive()) {
code.append(StringUtils.replace("(({})value).{}Value()", primitiveWrapMap.get(componentType), componentType.getCanonicalName()));
} else {
code.append(StringUtils.replace("({})value", componentType.getCanonicalName()));
}
code.append(";\n")
.append("}");
return code.toString();
}
private String createArrayGetCode(Class<?> clazz) {
StringBuilder code = new StringBuilder();
code.append("public Object get(Object array, int index){\n")
.append("\treturn ");
Class<?> componentType = clazz.getComponentType();
boolean hasValueOf = false;
if(componentType.isPrimitive()) {
code.append(StringUtils.replace("(Object){}.valueOf(", primitiveWrapMap.get(componentType)));
hasValueOf = true;
}
code.append(StringUtils.replace("(({})array)[index]", clazz.getCanonicalName()));
if(hasValueOf)
code.append(")");
code.append(";\n")
.append("}");
return code.toString();
}
private String createArraySizeCode(Class<?> clazz) {
StringBuilder code = new StringBuilder();
code.append("public int size(Object array){\n")
.append("\treturn ").append(StringUtils.replace("(({})array).length;\n", clazz.getCanonicalName()))
.append("}");
return code.toString();
}
}