/*
* Copyright 2002-2009 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
*
* 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.springframework.expression;
/**
* MethodExecutors are built by the resolvers and can be cached by the infrastructure to repeat an operation quickly
* without going back to the resolvers. For example, the particular method to run on an object may be discovered by the
* reflection method resolver - it will then build a MethodExecutor that executes that method and the MethodExecutor can
* be reused without needing to go back to the resolver to discover the method again.
*
* <p>They can become stale, and in that case should throw an AccessException - this will cause the infrastructure to go
* back to the resolvers to ask for a new one.
*
* @author Andy Clement
* @since 3.0
*/
public interface MethodExecutor {
/**
* Execute a command using the specified arguments, and using the specified expression state.
* @param context the evaluation context in which the command is being executed
* @param target the target object of the call - null for static methods
* @param arguments the arguments to the executor, should match (in terms of number and type) whatever the
* command will need to run
* @return the value returned from execution
* @throws AccessException if there is a problem executing the command or the MethodExecutor is no longer valid
*/
TypedValue execute(EvaluationContext context, Object target, Object... arguments) throws AccessException;
}
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