Top Description Fields Constructors Methods
com.google.common.reflect

public abstract Class AbstractInvocationHandler

extends Object
implements InvocationHandler
Class Inheritance
All Implemented Interfaces
java.lang.reflect.InvocationHandler
Annotations
@ElementTypesAreNonnullByDefault
Imports
java.lang.reflect.InvocationHandler, .Method, .Proxy, java.util.Arrays, javax.annotation.CheckForNull, org.checkerframework.checker.nullness.qual.Nullable
Abstract implementation of InvocationHandler that handles Object#equals, Object#hashCode and Object#toString. For example: 
class Unsupported extends AbstractInvocationHandler {
  protected Object handleInvocation(Object proxy, Method method, Object[] args) {
    throw new UnsupportedOperationException();
  }
}

CharSequence unsupported = Reflection.newProxy(CharSequence.class, new Unsupported());
Author
Ben Yu
Since
12.0

Field Summary

Modifier and TypeField and Description
private static final Object[]
NO_ARGS

Constructor Summary

AccessConstructor and Description
public
AbstractInvocationHandler()

Method Summary

Modifier and TypeMethod and Description
public boolean
equals(Object
the reference object with which to compare.
obj)

Overrides java.lang.Object.equals.

By default delegates to Object#equals so instances are only equal if they are identical.
protected abstract Object
handleInvocation(Object proxy, Method method, @Nullable Object[] args)

invoke delegates to this method upon any method invocation on the proxy instance, except Object#equals, Object#hashCode and Object#toString.

public int
hashCode()

Overrides java.lang.Object.hashCode.

By default delegates to Object#hashCode.
public final Object
invoke(Object
the proxy instance that the method was invoked on
proxy, Method
the Method instance corresponding to the interface method invoked on the proxy instance. The declaring class of the Method object will be the interface that the method was declared in, which may be a superinterface of the proxy interface that the proxy class inherits the method through.
method, @Nullable Object[]
an array of objects containing the values of the arguments passed in the method invocation on the proxy instance, or null if interface method takes no arguments. Arguments of primitive types are wrapped in instances of the appropriate primitive wrapper class, such as java.lang.Integer or java.lang.Boolean.
args)

Implements java.lang.reflect.InvocationHandler.invoke.

Processes a method invocation on a proxy instance and returns the result.
private static boolean
isProxyOfSameInterfaces(Object arg, Class<?> proxyClass)

public String
toString()

Overrides java.lang.Object.toString.

By default delegates to Object#toString.
Inherited from java.lang.Object:
clonefinalizegetClassnotifynotifyAllwaitwaitwait

Field Detail

NO_ARGSback to summary
private static final Object[] NO_ARGS

Constructor Detail

AbstractInvocationHandlerback to summary
public AbstractInvocationHandler()

Method Detail

equalsback to summary
public boolean equals(Object obj)

Overrides java.lang.Object.equals.

By default delegates to Object#equals so instances are only equal if they are identical. proxy.equals(argument) returns true if:

  • proxy and argument are of the same type
  • and this method returns true for the InvocationHandler of argument

Subclasses can override this method to provide custom equality.

Parameters
obj:Object

Doc from java.lang.Object.equals.

the reference object with which to compare.

Returns:boolean

Doc from java.lang.Object.equals.

true if this object is the same as the obj argument; false otherwise.

Annotations
@Override
handleInvocationback to summary
protected abstract Object handleInvocation(Object proxy, Method method, @Nullable Object[] args) throws Throwable

invoke delegates to this method upon any method invocation on the proxy instance, except Object#equals, Object#hashCode and Object#toString. The result will be returned as the proxied method's return value.

Unlike invoke, args will never be null. When the method has no parameter, an empty array is passed in.

Annotations
@CheckForNull
hashCodeback to summary
public int hashCode()

Overrides java.lang.Object.hashCode.

By default delegates to Object#hashCode. The dynamic proxies' hashCode() will delegate to this method. Subclasses can override this method to provide custom equality.

Returns:int

Doc from java.lang.Object.hashCode.

a hash code value for this object

Annotations
@Override
invokeback to summary
public final Object invoke(Object proxy, Method method, @Nullable Object[] args) throws Throwable

Implements java.lang.reflect.InvocationHandler.invoke.

Doc from java.lang.reflect.InvocationHandler.invoke.

Processes a method invocation on a proxy instance and returns the result. This method will be invoked on an invocation handler when a method is invoked on a proxy instance that it is associated with.

Parameters
proxy:Object

the proxy instance that the method was invoked on

method:Method

the Method instance corresponding to the interface method invoked on the proxy instance. The declaring class of the Method object will be the interface that the method was declared in, which may be a superinterface of the proxy interface that the proxy class inherits the method through.

args:@Nullable Object[]

an array of objects containing the values of the arguments passed in the method invocation on the proxy instance, or null if interface method takes no arguments. Arguments of primitive types are wrapped in instances of the appropriate primitive wrapper class, such as java.lang.Integer or java.lang.Boolean.

Returns:Object

the value to return from the method invocation on the proxy instance. If the declared return type of the interface method is a primitive type, then the value returned by this method must be an instance of the corresponding primitive wrapper class; otherwise, it must be a type assignable to the declared return type. If the value returned by this method is null and the interface method's return type is primitive, then a NullPointerException will be thrown by the method invocation on the proxy instance. If the value returned by this method is otherwise not compatible with the interface method's declared return type as described above, a ClassCastException will be thrown by the method invocation on the proxy instance.

Annotations
@Override
@CheckForNull
Exceptions
Throwable:
the exception to throw from the method invocation on the proxy instance. The exception's type must be assignable either to any of the exception types declared in the throws clause of the interface method or to the unchecked exception types java.lang.RuntimeException or java.lang.Error. If a checked exception is thrown by this method that is not assignable to any of the exception types declared in the throws clause of the interface method, then an UndeclaredThrowableException containing the exception that was thrown by this method will be thrown by the method invocation on the proxy instance.
isProxyOfSameInterfacesback to summary
private static boolean isProxyOfSameInterfaces(Object arg, Class<?> proxyClass)
toStringback to summary
public String toString()

Overrides java.lang.Object.toString.

By default delegates to Object#toString. The dynamic proxies' toString() will delegate to this method. Subclasses can override this method to provide custom string representation for the proxies.

Returns:String

Doc from java.lang.Object.toString.

a string representation of the object

Annotations
@Override