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
|
/*******************************************************************************
* Copyright (c) 2002, 2015 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.ui.internal.cheatsheets.registry;
import org.eclipse.core.runtime.*;
import org.eclipse.ui.internal.cheatsheets.*;
/**
* Template implementation of a registry reader that creates objects
* representing registry contents. Typically, an extension
* contains one element, but this reader handles multiple
* elements per extension.
*
* To start reading the extensions from the registry for an
* extension point, call the method <code>readRegistry</code>.
*
* To read children of an IConfigurationElement, call the
* method <code>readElementChildren</code> from your implementation
* of the method <code>readElement</code>, as it will not be
* done by default.
*/
public abstract class RegistryReader {
protected static final String TAG_DESCRIPTION = "description"; //$NON-NLS-1$
/**
* The constructor.
*/
/*package*/ RegistryReader() {
}
/**
* This method extracts description as a subelement of
* the given element.
* @return description string if defined, or empty string
* if not.
*/
/*package*/ String getDescription(IConfigurationElement config) {
IConfigurationElement[] children = config.getChildren(TAG_DESCRIPTION);
if (children.length >= 1) {
return children[0].getValue();
}
return ICheatSheetResource.EMPTY_STRING;
}
/**
* Logs the error in the workbench log using the provided
* text and the information in the configuration element.
*/
private void logError(IConfigurationElement element, String text) {
IExtension extension = element.getDeclaringExtension();
StringBuffer buf = new StringBuffer();
buf.append("Plugin " + extension.getContributor().getName() + ", extension " + extension.getExtensionPointUniqueIdentifier()); //$NON-NLS-2$//$NON-NLS-1$
buf.append("\n" + text); //$NON-NLS-1$
IStatus status = new Status(IStatus.ERROR, ICheatSheetResource.CHEAT_SHEET_PLUGIN_ID, IStatus.OK, buf.toString(), null);
CheatSheetPlugin.getPlugin().getLog().log(status);
}
/**
* Logs a very common registry error when a required attribute is missing.
*/
/*package*/ void logMissingAttribute(IConfigurationElement element, String attributeName) {
logError(element, "Required attribute '" + attributeName + "' not defined"); //$NON-NLS-2$//$NON-NLS-1$
}
/**
* Logs a registry error when the configuration element is unknown.
*/
private void logUnknownElement(IConfigurationElement element) {
logError(element, "Unknown extension tag found: " + element.getName()); //$NON-NLS-1$
}
/**
* Apply a reproducable order to the list of extensions
* provided, such that the order will not change as
* extensions are added or removed.
*/
private IExtension[] orderExtensions(IExtension[] extensions) {
// By default, the order is based on plugin id sorted
// in ascending order. The order for a plugin providing
// more than one extension for an extension point is
// dependent in the order listed in the XML file.
Sorter sorter = new Sorter() {
@Override
public boolean compare(Object extension1, Object extension2) {
String s1 = ((IExtension) extension1).getContributor().getName().toUpperCase();
String s2 = ((IExtension) extension2).getContributor().getName().toUpperCase();
//Return true if elementTwo is 'greater than' elementOne
return s2.compareTo(s1) > 0;
}
};
Object[] sorted = sorter.sort(extensions);
IExtension[] sortedExtension = new IExtension[sorted.length];
System.arraycopy(sorted, 0, sortedExtension, 0, sorted.length);
return sortedExtension;
}
/**
* Implement this method to read element's attributes.
* If children should also be read, then implementor
* is responsible for calling <code>readElementChildren</code>.
* Implementor is also responsible for logging missing
* attributes.
*
* @return true if element was recognized, false if not.
*/
/*package*/ abstract boolean readElement(IConfigurationElement element);
/**
* Read the element's children. This is called by
* the subclass' readElement method when it wants
* to read the children of the element.
*/
/*package*/ void readElementChildren(IConfigurationElement element) {
readElements(element.getChildren());
}
/**
* Read each element one at a time by calling the
* subclass implementation of <code>readElement</code>.
*
* Logs an error if the element was not recognized.
*/
private void readElements(IConfigurationElement[] elements) {
for (int i = 0; i < elements.length; i++) {
if (!readElement(elements[i]))
logUnknownElement(elements[i]);
}
}
/**
* Read one extension by looping through its
* configuration elements.
*/
private void readExtension(IExtension extension) {
readElements(extension.getConfigurationElements());
}
/**
* Start the registry reading process using the
* supplied plugin ID and extension point.
*/
/*package*/ void readRegistry(IExtensionRegistry registry, String pluginId, String extensionPoint) {
IExtensionPoint point = registry.getExtensionPoint(pluginId, extensionPoint);
if (point != null) {
IExtension[] extensions = point.getExtensions();
extensions = orderExtensions(extensions);
for (int i = 0; i < extensions.length; i++)
readExtension(extensions[i]);
}
}
}
|
