001/** 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018 019package org.apache.oozie.util.db; 020 021import java.util.HashSet; 022import java.util.Set; 023 024import com.google.common.base.Predicate; 025 026public abstract class DatabaseRetryPredicate implements Predicate<Throwable> { 027 028 @Override 029 public abstract boolean apply(Throwable input); 030 031 /* 032 * Helper method for subclasses to retrieve all exceptions in a set. "All exceptions" means the exception 033 * hierarchy that can be walked by calling getCause() repeatedly. 034 * 035 * Subclasses either check if a particular exception was raised or not, or need the SQLException to extract the 036 * error code. In both cases the exception has to be found. 037 */ 038 protected Set<Class<?>> getAllExceptions(final Throwable t) { 039 final Set<Class<?>> exceptions = new HashSet<>(); 040 041 exceptions.add(t.getClass()); 042 043 Throwable ex = t; 044 while (ex.getCause() != null) { 045 exceptions.add(ex.getCause().getClass()); 046 ex = ex.getCause(); 047 } 048 049 return exceptions; 050 } 051}