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Java > Open Source Codes > org > apache > ws > jaxme > js > DirectAccessible


1 /*
2  * Copyright 2003, 2004 The Apache Software Foundation
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.apache.ws.jaxme.js;
18
19 /** <p>This interface is an abstract base for fields and similar
20  * objects. It doesn't define many methods, it mainly indicates, that
21  * the implementations value is directly and fast accessible in
22  * the generated code. The use is best demonstrated by an example.
23  * Suggest the following piece of code:</p>
24  * <pre>
25  * Object value;
26  * return new Object[]{"((", value, ") * (", value, "))"};
27  * </pre>
28  * <p>The example is well suited for the case, where <code>value</code>
29  * is a variable name like "i". It is not suited, if "value" contains
30  * an expensive method call like "sin(x)". It is even wrong in the
31  * case "i++".</p>
32  * <p>By using the interface <code>DirectAccessible</code>, you can
33  * change the implementation of <code>getSquare()</code> to look
34  * like this:
35  * <pre>
36  * Object value;
37  * JavaQName type;
38  * if (!(value instanceof DirectAccessible)) {
39  * LocalJavaField v = pMethod.newJavaField(type);
40  * v.addLine(value);
41  * v.setFinal(true);
42  * value = v;
43  * }
44  * return new Object[]{"((", value, ") * (", value, "))"};
45  * </pre>
46  * <p>This results in code, which is far more readable and better
47  * optimized.</p>
48  *
49  * @author <a HREF="mailto:jwi@softwareag.com">Jochen Wiedmann</a>
50  */
51 public interface DirectAccessible extends TypedValue {
52    /** <p>Returns whether the value is possibly null.</p>
53     */
54    public boolean isNullable();
55    /** <p>Sets whether the value is possibly null.</p>
56     */
57    public void setNullable(boolean pNullable);
58 }
59
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