1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
|
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.apache.tools.ant;
import java.lang.reflect.Method;
import org.apache.tools.ant.dispatch.DispatchUtils;
import org.apache.tools.ant.dispatch.Dispatchable;
/**
* Uses introspection to "adapt" an arbitrary Bean which doesn't
* itself extend Task, but still contains an execute method and optionally
* a setProject method.
*
*/
public class TaskAdapter extends Task implements TypeAdapter {
/** Object to act as a proxy for. */
private Object proxy;
/**
* No-arg constructor for reflection.
*/
public TaskAdapter() {
}
/**
* Constructor for given proxy.
* So you could write easier code
* <pre>
* myTaskContainer.addTask( new TaskAdapter(myProxy) );
* </pre>
*
* @param proxy The object which Ant should use as task.
*/
public TaskAdapter(Object proxy) {
this();
setProxy(proxy);
}
/**
* Checks whether or not a class is suitable to be adapted by TaskAdapter.
* If the class is of type Dispatchable, the check is not performed because
* the method that will be executed will be determined only at runtime of
* the actual task and not during parse time.
*
* This only checks conditions which are additionally required for
* tasks adapted by TaskAdapter. Thus, this method should be called by
* Project.checkTaskClass.
*
* Throws a BuildException and logs as Project.MSG_ERR for
* conditions that will cause the task execution to fail.
* Logs other suspicious conditions with Project.MSG_WARN.
*
* @param taskClass Class to test for suitability.
* Must not be <code>null</code>.
* @param project Project to log warnings/errors to.
* Must not be <code>null</code>.
*
* @see Project#checkTaskClass(Class)
*/
public static void checkTaskClass(final Class<?> taskClass,
final Project project) {
if (!Dispatchable.class.isAssignableFrom(taskClass)) {
// don't have to check for interface, since then
// taskClass would be abstract too.
try {
final Method executeM = taskClass.getMethod("execute", (Class[]) null);
// don't have to check for public, since
// getMethod finds public method only.
// don't have to check for abstract, since then
// taskClass would be abstract too.
if (!Void.TYPE.equals(executeM.getReturnType())) {
final String message = "return type of execute() should be "
+ "void but was \"" + executeM.getReturnType() + "\" in "
+ taskClass;
project.log(message, Project.MSG_WARN);
}
} catch (NoSuchMethodException e) {
final String message = "No public execute() in " + taskClass;
project.log(message, Project.MSG_ERR);
throw new BuildException(message);
} catch (LinkageError e) {
String message = "Could not load " + taskClass + ": " + e;
project.log(message, Project.MSG_ERR);
throw new BuildException(message, e);
}
}
}
/**
* Check if the proxy class is a valid class to use
* with this adapter.
* The class must have a public no-arg "execute()" method.
* @param proxyClass the class to check.
*/
public void checkProxyClass(Class<?> proxyClass) {
checkTaskClass(proxyClass, getProject());
}
/**
* Executes the proxied task.
*
* @exception BuildException if the project could not be set
* or the method could not be executed.
*/
public void execute() throws BuildException {
try {
Method setLocationM = proxy.getClass().getMethod(
"setLocation", new Class[] {Location.class});
if (setLocationM != null) {
setLocationM.invoke(proxy, new Object[] {getLocation()});
}
} catch (NoSuchMethodException e) {
// ignore this if the class being used as a task does not have
// a set location method.
} catch (Exception ex) {
log("Error setting location in " + proxy.getClass(),
Project.MSG_ERR);
throw new BuildException(ex);
}
try {
Method setProjectM = proxy.getClass().getMethod(
"setProject", new Class[] {Project.class});
if (setProjectM != null) {
setProjectM.invoke(proxy, new Object[] {getProject()});
}
} catch (NoSuchMethodException e) {
// ignore this if the class being used as a task does not have
// a set project method.
} catch (Exception ex) {
log("Error setting project in " + proxy.getClass(),
Project.MSG_ERR);
throw new BuildException(ex);
}
try {
DispatchUtils.execute(proxy);
} catch (BuildException be) {
throw be;
} catch (Exception ex) {
log("Error in " + proxy.getClass(), Project.MSG_VERBOSE);
throw new BuildException(ex);
}
}
/**
* Sets the target object to proxy for.
*
* @param o The target object. Must not be <code>null</code>.
*/
public void setProxy(Object o) {
this.proxy = o;
}
/**
* Returns the target object being proxied.
*
* @return the target proxy object.
*/
public Object getProxy() {
return proxy;
}
}
|
