| 1 | /* |
| 2 | * Copyright 2006-2007 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.batch.repeat.exception; |
| 18 | |
| 19 | import java.util.HashMap; |
| 20 | |
| 21 | import org.springframework.batch.repeat.RepeatContext; |
| 22 | import org.springframework.batch.support.ExceptionClassifierSupport; |
| 23 | |
| 24 | /** |
| 25 | * Simple implementation of exception handler which looks for given exception |
| 26 | * types. If one of the types is found then a counter is incremented and the |
| 27 | * limit is checked to determine if it has been exceeded and the Throwable |
| 28 | * should be re-thrown. Also allows to specify list of 'fatal' exceptions that |
| 29 | * are never subject to counting, but are immediately re-thrown. The fatal list |
| 30 | * has higher priority so the two lists needn't be exclusive. |
| 31 | * |
| 32 | * @author Dave Syer |
| 33 | * @author Robert Kasanicky |
| 34 | */ |
| 35 | public class SimpleLimitExceptionHandler implements ExceptionHandler { |
| 36 | |
| 37 | /** |
| 38 | * Name of exception classifier key for the nominated exception types. |
| 39 | */ |
| 40 | private static final String TX_INVALID = "TX_INVALID"; |
| 41 | |
| 42 | /** |
| 43 | * Name of exception classifier key for the fatal exception types (not |
| 44 | * counted, immediately rethrown). |
| 45 | */ |
| 46 | private static final String FATAL = "FATAL"; |
| 47 | |
| 48 | private RethrowOnThresholdExceptionHandler delegate = new RethrowOnThresholdExceptionHandler(); |
| 49 | |
| 50 | private Class[] exceptionClasses = new Class[] { Exception.class }; |
| 51 | |
| 52 | private Class[] fatalExceptionClasses = new Class[] { Error.class }; |
| 53 | |
| 54 | /** |
| 55 | * Flag to indicate the the exception counters should be shared between |
| 56 | * sibling contexts in a nested batch (i.e. inner loop). Default is false. |
| 57 | * Set this flag to true if you want to count exceptions for the whole |
| 58 | * (outer) loop in a typical container. |
| 59 | * |
| 60 | * @param useParent true if the parent context should be used to store the |
| 61 | * counters. |
| 62 | */ |
| 63 | public void setUseParent(boolean useParent) { |
| 64 | delegate.setUseParent(useParent); |
| 65 | } |
| 66 | |
| 67 | /** |
| 68 | * Convenience constructor for the {@link SimpleLimitExceptionHandler} to |
| 69 | * set the limit. |
| 70 | */ |
| 71 | public SimpleLimitExceptionHandler(int limit) { |
| 72 | this(); |
| 73 | setLimit(limit); |
| 74 | } |
| 75 | |
| 76 | /** |
| 77 | * Default constructor for the {@link SimpleLimitExceptionHandler}. |
| 78 | */ |
| 79 | public SimpleLimitExceptionHandler() { |
| 80 | super(); |
| 81 | delegate.setExceptionClassifier(new ExceptionClassifierSupport() { |
| 82 | public Object classify(Throwable throwable) { |
| 83 | for (int i = 0; i < fatalExceptionClasses.length; i++) { |
| 84 | if (fatalExceptionClasses[i].isAssignableFrom(throwable.getClass())) { |
| 85 | return FATAL; |
| 86 | } |
| 87 | } |
| 88 | for (int i = 0; i < exceptionClasses.length; i++) { |
| 89 | if (exceptionClasses[i].isAssignableFrom(throwable.getClass())) { |
| 90 | return TX_INVALID; |
| 91 | } |
| 92 | } |
| 93 | return super.classify(throwable); |
| 94 | } |
| 95 | }); |
| 96 | } |
| 97 | |
| 98 | /** |
| 99 | * Rethrows only if the limit is breached for this context on the exception |
| 100 | * type specified. |
| 101 | * |
| 102 | * @see #setExceptionClasses(Class[]) |
| 103 | * @see #setLimit(int) |
| 104 | * |
| 105 | * @see org.springframework.batch.repeat.exception.ExceptionHandler#handleException(org.springframework.batch.repeat.RepeatContext, |
| 106 | * Throwable) |
| 107 | */ |
| 108 | public void handleException(RepeatContext context, Throwable throwable) throws Throwable { |
| 109 | delegate.handleException(context, throwable); |
| 110 | } |
| 111 | |
| 112 | /** |
| 113 | * The limit on the given exception type within a single context before it |
| 114 | * is rethrown. |
| 115 | * |
| 116 | * @param limit |
| 117 | */ |
| 118 | public void setLimit(final int limit) { |
| 119 | delegate.setThresholds(new HashMap() { |
| 120 | { |
| 121 | put(ExceptionClassifierSupport.DEFAULT, new Integer(0)); |
| 122 | put(TX_INVALID, new Integer(limit)); |
| 123 | put(FATAL, new Integer(0)); |
| 124 | } |
| 125 | }); |
| 126 | } |
| 127 | |
| 128 | /** |
| 129 | * Setter for the Throwable exceptionClasses that this handler counts. |
| 130 | * Defaults to {@link Exception}. If more exceptionClasses are specified |
| 131 | * handler uses single counter that is incremented when one of the |
| 132 | * recognized exception exceptionClasses is handled. |
| 133 | */ |
| 134 | public void setExceptionClasses(Class[] classes) { |
| 135 | this.exceptionClasses = classes; |
| 136 | } |
| 137 | |
| 138 | /** |
| 139 | * Setter for the Throwable exceptionClasses that shouldn't be counted, but |
| 140 | * rethrown immediately. This list has higher priority than |
| 141 | * {@link #setExceptionClasses(Class[])}. |
| 142 | * |
| 143 | * @param fatalExceptionClasses defaults to {@link Error} |
| 144 | */ |
| 145 | public void setFatalExceptionClasses(Class[] fatalExceptionClasses) { |
| 146 | this.fatalExceptionClasses = fatalExceptionClasses; |
| 147 | } |
| 148 | |
| 149 | } |