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 package org.apache.oozie.workflow.lite; 019 020 021 import org.apache.oozie.workflow.WorkflowException; 022 import org.apache.oozie.util.ParamChecker; 023 import org.apache.oozie.ErrorCode; 024 025 import java.util.ArrayList; 026 import java.util.List; 027 028 /** 029 * Workflow lite start node definition. 030 */ 031 public class StartNodeDef extends NodeDef { 032 033 /** 034 * Reserved name fo the start node. <p/> It is an invalid token, it will never match an application node name. 035 */ 036 public static final String START = "::start::"; 037 038 /** 039 * Default constructor. 040 */ 041 public StartNodeDef() { 042 } 043 044 /** 045 * Create a start node definition. 046 * 047 * @param transitionTo transition on workflow start. 048 */ 049 public StartNodeDef(String transitionTo) { 050 super(START, null, StartNodeHandler.class, createList(ParamChecker.notEmpty(transitionTo, "transitionTo"))); 051 } 052 053 private static List<String> createList(String transition) { 054 List<String> list = new ArrayList<String>(); 055 list.add(transition); 056 return list; 057 } 058 059 /** 060 * Start node handler. <p/> It does an immediate transition to the transitionTo node. 061 */ 062 public static class StartNodeHandler extends NodeHandler { 063 064 public boolean enter(Context context) throws WorkflowException { 065 if (!context.getSignalValue().equals(StartNodeDef.START)) { 066 throw new WorkflowException(ErrorCode.E0715, context.getSignalValue()); 067 } 068 return true; 069 } 070 071 public String exit(Context context) { 072 return context.getNodeDef().getTransitions().get(0); 073 } 074 075 public void kill(Context context) { 076 } 077 078 public void fail(Context context) { 079 } 080 } 081 082 }