blob: e187919b30f9d1c5a1c7c0344ad1f8e774b7e00f (
plain) (
blame)
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
|
/*
* Copyright (c) 2007, 2009, 2011, 2012 Eike Stepper (Berlin, Germany) 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:
* Eike Stepper - initial API and implementation
* Christian W. Damus (CEA LIST) - bug 399306 - adapted from SafeActionDelegate
*/
package org.eclipse.net4j.util.ui.handlers;
import org.eclipse.net4j.util.internal.ui.bundle.OM;
import org.eclipse.net4j.util.internal.ui.messages.Messages;
import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.Command;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.commands.common.NotDefinedException;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.ui.ISources;
import org.eclipse.ui.handlers.HandlerUtil;
/**
* @author Eike Stepper
* @author Christian W. Damus (CEA LIST)
*
* @since 3.4
*/
public abstract class SafeHandler extends AbstractHandler
{
private Command command;
private ISelection selection;
public SafeHandler()
{
}
public Command getCommand()
{
return command;
}
public ISelection getSelection()
{
return selection;
}
public Object execute(ExecutionEvent event) throws ExecutionException
{
Object result = null;
try
{
extractEventDetails(event);
result = safeExecute(event);
}
catch (ExecutionException ex)
{
throw ex;
}
catch (Exception ex)
{
OM.LOG.error(ex);
MessageDialog.openError(null, getText(),
ex.getLocalizedMessage() + "\n" + Messages.getString("SafeActionDelegate_0")); //$NON-NLS-1$ //$NON-NLS-2$
}
return result;
}
@Override
public void setEnabled(Object evaluationContext)
{
Object variable = HandlerUtil.getVariable(evaluationContext, ISources.ACTIVE_CURRENT_SELECTION_NAME);
selection = variable instanceof ISelection ? (ISelection)variable : StructuredSelection.EMPTY;
setBaseEnabled(updateSelection(selection));
}
/**
* Extracts details from the {@code event} that we may need later,
* for example on a background thread when the original execution
* context is no longer valid.
*/
protected void extractEventDetails(ExecutionEvent event)
{
setEnabled(event.getApplicationContext());
command = event.getCommand();
}
protected abstract Object safeExecute(ExecutionEvent event) throws Exception;
protected String getText()
{
try
{
return command == null ? Messages.getString("SafeActionDelegate_1") : command.getName(); //$NON-NLS-1$
}
catch (NotDefinedException e)
{
return Messages.getString("SafeActionDelegate_1"); //$NON-NLS-1$
}
}
protected boolean updateSelection(ISelection selection)
{
return true;
}
}
|