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	/*
	* Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package java.lang.invoke;

	import java.io.Serializable;
	import java.lang.reflect.Method;
	import java.security.AccessController;
	import java.security.PrivilegedActionException;
	import java.security.PrivilegedExceptionAction;
	import java.util.Objects;

	/**
	* Serialized form of a lambda expression. The properties of this class
	* represent the information that is present at the lambda factory site, including
	* static metafactory arguments such as the identity of the primary functional
	* interface method and the identity of the implementation method, as well as
	* dynamic metafactory arguments such as values captured from the lexical scope
	* at the time of lambda capture.
	*
	* <p>Implementors of serializable lambdas, such as compilers or language
	* runtime libraries, are expected to ensure that instances deserialize properly.
	* One means to do so is to ensure that the {@code writeReplace} method returns
	* an instance of {@code SerializedLambda}, rather than allowing default
	* serialization to proceed.
	*
	* <p>{@code SerializedLambda} has a {@code readResolve} method that looks for
	* a (possibly private) static method called
	* {@code $deserializeLambda$(SerializedLambda)} in the capturing class, invokes
	* that with itself as the first argument, and returns the result. Lambda classes
	* implementing {@code $deserializeLambda$} are responsible for validating
	* that the properties of the {@code SerializedLambda} are consistent with a
	* lambda actually captured by that class.
	*
	* @see LambdaMetafactory
	*/
	public final class SerializedLambda implements Serializable {
	private static final long serialVersionUID = 8025925345765570181L;
	private final Class<?> capturingClass;
	private final String functionalInterfaceClass;
	private final String functionalInterfaceMethodName;
	private final String functionalInterfaceMethodSignature;
	private final String implClass;
	private final String implMethodName;
	private final String implMethodSignature;
	private final int implMethodKind;
	private final String instantiatedMethodType;
	private final Object[] capturedArgs;

	/**
	* Create a {@code SerializedLambda} from the low-level information present
	* at the lambda factory site.
	*
	* @param capturingClass The class in which the lambda expression appears
	* @param functionalInterfaceClass Name, in slash-delimited form, of static
	* type of the returned lambda object
	* @param functionalInterfaceMethodName Name of the functional interface
	* method for the present at the
	* lambda factory site
	* @param functionalInterfaceMethodSignature Signature of the functional
	* interface method present at
	* the lambda factory site
	* @param implMethodKind Method handle kind for the implementation method
	* @param implClass Name, in slash-delimited form, for the class holding
	* the implementation method
	* @param implMethodName Name of the implementation method
	* @param implMethodSignature Signature of the implementation method
	* @param instantiatedMethodType The signature of the primary functional
	* interface method after type variables
	* are substituted with their instantiation
	* from the capture site
	* @param capturedArgs The dynamic arguments to the lambda factory site,
	* which represent variables captured by
	* the lambda
	*/
	public SerializedLambda(Class<?> capturingClass,
	String functionalInterfaceClass,
	String functionalInterfaceMethodName,
	String functionalInterfaceMethodSignature,
	int implMethodKind,
	String implClass,
	String implMethodName,
	String implMethodSignature,
	String instantiatedMethodType,
	Object[] capturedArgs) {
	this.capturingClass = capturingClass;
	this.functionalInterfaceClass = functionalInterfaceClass;
	this.functionalInterfaceMethodName = functionalInterfaceMethodName;
	this.functionalInterfaceMethodSignature = functionalInterfaceMethodSignature;
	this.implMethodKind = implMethodKind;
	this.implClass = implClass;
	this.implMethodName = implMethodName;
	this.implMethodSignature = implMethodSignature;
	this.instantiatedMethodType = instantiatedMethodType;
	this.capturedArgs = Objects.requireNonNull(capturedArgs).clone();
	}

	/**
	* Get the name of the class that captured this lambda.
	* @return the name of the class that captured this lambda
	*/
	public String getCapturingClass() {
	return capturingClass.getName().replace('.', '/');
	}

	/**
	* Get the name of the invoked type to which this
	* lambda has been converted
	* @return the name of the functional interface class to which
	* this lambda has been converted
	*/
	public String getFunctionalInterfaceClass() {
	return functionalInterfaceClass;
	}

	/**
	* Get the name of the primary method for the functional interface
	* to which this lambda has been converted.
	* @return the name of the primary methods of the functional interface
	*/
	public String getFunctionalInterfaceMethodName() {
	return functionalInterfaceMethodName;
	}

	/**
	* Get the signature of the primary method for the functional
	* interface to which this lambda has been converted.
	* @return the signature of the primary method of the functional
	* interface
	*/
	public String getFunctionalInterfaceMethodSignature() {
	return functionalInterfaceMethodSignature;
	}

	/**
	* Get the name of the class containing the implementation
	* method.
	* @return the name of the class containing the implementation
	* method
	*/
	public String getImplClass() {
	return implClass;
	}

	/**
	* Get the name of the implementation method.
	* @return the name of the implementation method
	*/
	public String getImplMethodName() {
	return implMethodName;
	}

	/**
	* Get the signature of the implementation method.
	* @return the signature of the implementation method
	*/
	public String getImplMethodSignature() {
	return implMethodSignature;
	}

	/**
	* Get the method handle kind (see {@link MethodHandleInfo}) of
	* the implementation method.
	* @return the method handle kind of the implementation method
	*/
	public int getImplMethodKind() {
	return implMethodKind;
	}

	/**
	* Get the signature of the primary functional interface method
	* after type variables are substituted with their instantiation
	* from the capture site.
	* @return the signature of the primary functional interface method
	* after type variable processing
	*/
	public final String getInstantiatedMethodType() {
	return instantiatedMethodType;
	}

	/**
	* Get the count of dynamic arguments to the lambda capture site.
	* @return the count of dynamic arguments to the lambda capture site
	*/
	public int getCapturedArgCount() {
	return capturedArgs.length;
	}

	/**
	* Get a dynamic argument to the lambda capture site.
	* @param i the argument to capture
	* @return a dynamic argument to the lambda capture site
	*/
	public Object getCapturedArg(int i) {
	return capturedArgs[i];
	}

	private Object readResolve() throws ReflectiveOperationException {
	try {
	Method deserialize = AccessController.doPrivileged(new PrivilegedExceptionAction<Method>() {
	@Override
	public Method run() throws Exception {
	Method m = capturingClass.getDeclaredMethod("$deserializeLambda$", SerializedLambda.class);
	m.setAccessible(true);
	return m;
	}
	});

	return deserialize.invoke(null, this);
	}
	catch (PrivilegedActionException e) {
	Exception cause = e.getException();
	if (cause instanceof ReflectiveOperationException)
	throw (ReflectiveOperationException) cause;
	else if (cause instanceof RuntimeException)
	throw (RuntimeException) cause;
	else
	throw new RuntimeException("Exception in SerializedLambda.readResolve", e);
	}
	}

	@Override
	public String toString() {
	String implKind=MethodHandleInfo.referenceKindToString(implMethodKind);
	return String.format("SerializedLambda[%s=%s, %s=%s.%s:%s, " +
	"%s=%s %s.%s:%s, %s=%s, %s=%d]",
	"capturingClass", capturingClass,
	"functionalInterfaceMethod", functionalInterfaceClass,
	functionalInterfaceMethodName,
	functionalInterfaceMethodSignature,
	"implementation",
	implKind,
	implClass, implMethodName, implMethodSignature,
	"instantiatedMethodType", instantiatedMethodType,
	"numCaptured", capturedArgs.length);
	}
	}

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