1 /* 2 * Copyright 2002-2012 the original author or authors. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package org.springframework.aop.support; 18 19 import java.io.Serializable; 20 21 /** 22 * Abstract superclass for expression pointcuts, 23 * offering location and expression properties. 24 * 25 * @author Rod Johnson 26 * @author Rob Harrop 27 * @since 2.0 28 * @see #setLocation 29 * @see #setExpression 30 */ 31 @SuppressWarnings("serial") 32 public abstract class AbstractExpressionPointcut implements ExpressionPointcut, Serializable { 33 34 private String location; 35 36 private String expression; 37 38 39 /** 40 * Set the location for debugging. 41 */ 42 public void setLocation(String location) { 43 this.location = location; 44 } 45 46 /** 47 * Return location information about the pointcut expression 48 * if available. This is useful in debugging. 49 * @return location information as a human-readable String, 50 * or {@code null} if none is available 51 */ 52 public String getLocation() { 53 return this.location; 54 } 55 56 public void setExpression(String expression) { 57 this.expression = expression; 58 try { 59 onSetExpression(expression); 60 } 61 catch (IllegalArgumentException ex) { 62 // Fill in location information if possible. 63 if (this.location != null) { 64 throw new IllegalArgumentException("Invalid expression at location [" + this.location + "]: " + ex); 65 } 66 else { 67 throw ex; 68 } 69 } 70 } 71 72 /** 73 * Called when a new pointcut expression is set. 74 * The expression should be parsed at this point if possible. 75 * <p>This implementation is empty. 76 * @param expression expression to set 77 * @throws IllegalArgumentException if the expression is invalid 78 * @see #setExpression 79 */ 80 protected void onSetExpression(String expression) throws IllegalArgumentException { 81 } 82 83 /** 84 * Return this pointcut's expression. 85 */ 86 @Override 87 public String getExpression() { 88 return this.expression; 89 } 90 91 }