Question

正如标题中所解释的，我正在尝试使用批处理IResourceChangeEvents的方法创建IMarkers。我的目标是以正确，稳定的方式创建IMarkers。使用IWorkspaceRunnable是否存在任何限制（用于批量更改事件），还是在当前线程中创建IMarkers更安全？是否存在任何可预见的错误，例如并发问题？

这是一个开放式问题，但我只想了解使用IWorkspaceRunnable创建IMarkers的优缺点。以下是代码示例，包括和不包含批次更改：

// Generates marker with the given attributes
public static IMarker generateMarker(final IFile file, final Map<String, Object>     attributes,
                                   final String markerType) throws CoreException, BadLocationException, IOException
{
    if (!attributes.containsKey(IMarker.LINE_NUMBER))
    {
        // Assumes that attributes has a mapping for IMarker.CHAR_START, which is invariant when creating markers in Solstice
        int line = ResourceUtility.convertToDocument(file).getLineOfOffset((int) attributes.get(IMarker.CHAR_START));
        attributes.put(IMarker.LINE_NUMBER, line + 1); // lines indexed at 1, not 0
    }

    IWorkspaceRunnable r = new IWorkspaceRunnable()
    {
        public void run(@Nullable IProgressMonitor monitor) throws CoreException
        {
            IMarker marker = file.createMarker(markerType);
            marker.setAttributes(attributes);

            MarkerField.marker_ = marker; // MarkerField is just an inner class. Functions as a pointer to a pointer.
        }
    };
    file.getWorkspace().run(r, ResourceUtility.getRuleFactory().markerRule(file), 0, null);
    return MarkerField.marker_;
}

或者，我可以取消批处理机制，并使用以下代码：

// Generates marker with the given attributes
public static IMarker generateMarker(final IFile file, final Map<String, Object>     attributes,
                                   final String markerType) throws CoreException, BadLocationException, IOException
{
    if (!attributes.containsKey(IMarker.LINE_NUMBER))
    {
        // Assumes that attributes has a mapping for IMarker.CHAR_START, which is invariant when creating markers in Solstice
        int line = ResourceUtility.convertToDocument(file).getLineOfOffset((int) attributes.get(IMarker.CHAR_START));
        attributes.put(IMarker.LINE_NUMBER, line + 1); // lines indexed at 1, not 0
    }

    IMarker marker = file.createMarker(markerType);
    marker.setAttributes(attributes);

    return marker;
}

每种方法的优点/缺点是什么？

Answer 1

事实证明，使用IWorkspaceRunnable进行批量更改是安全的。以下是一些消息来源：

Eclipse社区论坛帖子讨论了这个问题： http://www.eclipse.org/forums/index.php/m/126939/?srch=batching+resource#msg_126939

使用相同机制的MarkerUtilities类几乎与我上面的代码相似。摘录如下。

我现在唯一的问题是访问我刚创建的IMarker是否安全并返回它。我认为这是可以的，因为在返回IMarker时，IWorkspaceRunnable线程已经完成。

/**
 * Creates a marker on the given resource with the given type and attributes.
 * <p>
 * This method modifies the workspace (progress is not reported to the user).</p>
 *
 * @param resource the resource
 * @param attributes the attribute map (key type: <code>String</code>,
 *   value type: <code>Object</code>)
 * @param markerType the type of marker
 * @throws CoreException if this method fails
 * @see IResource#createMarker(java.lang.String)
 */
public static void createMarker(final IResource resource, final Map attributes, final String markerType) throws CoreException {

    IWorkspaceRunnable r= new IWorkspaceRunnable() {
        public void run(IProgressMonitor monitor) throws CoreException {
            IMarker marker= resource.createMarker(markerType);
            marker.setAttributes(attributes);
        }
    };

    resource.getWorkspace().run(r, null,IWorkspace.AVOID_UPDATE, null);
}

使用Eclipse PDE中的IWorkspaceRunnable对IResourceChangeEvenets进行批处理以生成imarker

1 个答案: