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1
16 package org.springframework.webflow.definition.registry;
17
18 import java.util.Iterator  ;
19 import java.util.LinkedList ;
20 import java.util.Map ;
21 import java.util.TreeMap ;
22
23 import org.springframework.core.style.ToStringCreator;
24 import org.springframework.util.Assert;
25 import org.springframework.webflow.definition.FlowDefinition;
26
27
35 public class FlowDefinitionRegistryImpl implements FlowDefinitionRegistry {
36
37
40 private Map flowDefinitions = new TreeMap ();
41
42
45 private FlowDefinitionRegistry parent;
46
47
49 public String [] getFlowDefinitionIds() {
50 return (String [])flowDefinitions.keySet().toArray(new String [flowDefinitions.size()]);
51 }
52
53 public int getFlowDefinitionCount() {
54 return flowDefinitions.size();
55 }
56
57 public boolean containsFlowDefinition(String id) {
58 Assert.hasText(id, "The flow id is required");
59 return flowDefinitions.get(id) != null;
60 }
61
62 public void refresh() throws FlowDefinitionConstructionException {
63 ClassLoader loader = Thread.currentThread().getContextClassLoader();
64 try {
65 Thread.currentThread().setContextClassLoader(getClass().getClassLoader());
67 LinkedList needsReindexing = new LinkedList ();
68 Iterator it = flowDefinitions.entrySet().iterator();
69 while (it.hasNext()) {
70 Map.Entry entry = (Map.Entry )it.next();
71 String key = (String )entry.getKey();
72 FlowDefinitionHolder holder = (FlowDefinitionHolder)entry.getValue();
73 holder.refresh();
74 if (!holder.getFlowDefinitionId().equals(key)) {
75 needsReindexing.add(new Indexed(key, holder));
76 }
77 }
78 it = needsReindexing.iterator();
79 while (it.hasNext()) {
80 Indexed indexed = (Indexed)it.next();
81 reindex(indexed.holder, indexed.key);
82 }
83 }
84 finally {
85 Thread.currentThread().setContextClassLoader(loader);
86 }
87 }
88
89 public void refresh(String flowId)
90 throws NoSuchFlowDefinitionException, FlowDefinitionConstructionException {
91 ClassLoader loader = Thread.currentThread().getContextClassLoader();
92 try {
93 Thread.currentThread().setContextClassLoader(getClass().getClassLoader());
95 FlowDefinitionHolder holder = getFlowDefinitionHolder(flowId);
96 holder.refresh();
97 if (!holder.getFlowDefinitionId().equals(flowId)) {
98 reindex(holder, flowId);
99 }
100 }
101 finally {
102 Thread.currentThread().setContextClassLoader(loader);
103 }
104 }
105
106
108 public FlowDefinition getFlowDefinition(String id)
109 throws NoSuchFlowDefinitionException, FlowDefinitionConstructionException {
110 Assert.hasText(id,
111 "Unable to load a flow definition: no flow id was provided. Please provide a valid flow identifier.");
112 try {
113 return getFlowDefinitionHolder(id).getFlowDefinition();
114 }
115 catch (NoSuchFlowDefinitionException e) {
116 if (parent != null) {
117 return parent.getFlowDefinition(id);
119 }
120 throw e;
121 }
122 }
123
124
126 public void setParent(FlowDefinitionRegistry parent) {
127 this.parent = parent;
128 }
129
130 public FlowDefinition[] getFlowDefinitions() throws FlowDefinitionConstructionException {
131 FlowDefinition[] flows = new FlowDefinition[flowDefinitions.size()];
132 Iterator it = flowDefinitions.values().iterator();
133 int i = 0;
134 while (it.hasNext()) {
135 FlowDefinitionHolder holder = (FlowDefinitionHolder)it.next();
136 flows[i] = holder.getFlowDefinition();
137 i++;
138 }
139 return flows;
140 }
141
142 public void registerFlowDefinition(FlowDefinitionHolder flowHolder) {
143 Assert.notNull(flowHolder, "The flow definition holder to register is required");
144 index(flowHolder);
145 }
146
147
152 public void removeFlowDefinition(String id) {
153 Assert.hasText(id, "The flow id is required");
154 flowDefinitions.remove(id);
155 }
156
157
159
164 private void reindex(FlowDefinitionHolder holder, String oldId) {
165 flowDefinitions.remove(oldId);
166 index(holder);
167 }
168
169
173 private void index(FlowDefinitionHolder holder) {
174 Assert.hasText(holder.getFlowDefinitionId(), "The flow holder to index must return a non-blank flow id");
175 flowDefinitions.put(holder.getFlowDefinitionId(), holder);
176 }
177
178
182 private FlowDefinitionHolder getFlowDefinitionHolder(String id) throws NoSuchFlowDefinitionException {
183 FlowDefinitionHolder flowHolder = (FlowDefinitionHolder)flowDefinitions.get(id);
184 if (flowHolder == null) {
185 throw new NoSuchFlowDefinitionException(id, getFlowDefinitionIds());
186 }
187 return flowHolder;
188 }
189
190
196 private static class Indexed {
197
198 private String key;
199
200 private FlowDefinitionHolder holder;
201
202 public Indexed(String key, FlowDefinitionHolder holder) {
203 this.key = key;
204 this.holder = holder;
205 }
206 }
207
208 public String toString() {
209 return new ToStringCreator(this).append("flowDefinitions", flowDefinitions).append("parent", parent).toString();
210 }
211 } |
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