--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwtx/jface/text/TextSelection.d	Sat Aug 23 19:10:48 2008 +0200
@@ -0,0 +1,191 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2005 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
+ * Port to the D programming language:
+ *     Frank Benoit <benoit@tionex.de>
+ *******************************************************************************/
+module dwtx.jface.text.TextSelection;
+
+import dwt.dwthelper.utils;
+
+
+/**
+ * Standard implementation of {@link dwtx.jface.text.ITextSelection}.
+ * <p>
+ * Makes advantage of the weak contract of correctness of its interface. If
+ * generated from a selection provider, it only remembers its offset and length
+ * and computes the remaining information on request.</p>
+ */
+public class TextSelection : ITextSelection {
+
+    /** Internal empty text selection */
+    private final static ITextSelection NULL= new TextSelection();
+
+    /**
+     * Returns a shared instance of an empty text selection.
+     *
+     * @return a shared instance of an empty text selection
+     */
+    public static ITextSelection emptySelection() {
+        return NULL;
+    }
+
+    /** Document which delivers the data of the selection */
+    private IDocument fDocument;
+    /** Offset of the selection */
+    private int fOffset;
+    /** Length of the selection */
+    private int fLength;
+
+
+    /**
+     * Creates an empty text selection.
+     */
+    private TextSelection() {
+        this(null, -1, -1);
+    }
+
+    /**
+     * Creates a text selection for the given range. This
+     * selection object describes generically a text range and
+     * is intended to be an argument for the <code>setSelection</code>
+     * method of selection providers.
+     *
+     * @param offset the offset of the range
+     * @param length the length of the range
+     */
+    public TextSelection(int offset, int length) {
+        this(null, offset, length);
+    }
+
+    /**
+     * Creates a text selection for the given range of the given document.
+     * This selection object is created by selection providers in responds
+     * <code>getSelection</code>.
+     *
+     * @param document the document whose text range is selected in a viewer
+     * @param offset the offset of the selected range
+     * @param length the length of the selected range
+     */
+    public TextSelection(IDocument document, int offset, int length) {
+        fDocument= document;
+        fOffset= offset;
+        fLength= length;
+    }
+
+    /**
+     *
+     * Returns true if the offset and length are smaller than 0.
+     * A selection of length 0, is a valid text selection as it
+     * describes, e.g., the cursor position in a viewer.
+     *
+     * @return <code>true</code> if this selection is empty
+     * @see dwtx.jface.viewers.ISelection#isEmpty()
+     */
+    public bool isEmpty() {
+        return fOffset < 0 || fLength < 0;
+    }
+
+    /*
+     * @see dwtx.jface.text.ITextSelection#getOffset()
+     */
+    public int getOffset() {
+        return fOffset;
+    }
+
+    /*
+     * @see dwtx.jface.text.ITextSelection#getLength()
+     */
+    public int getLength() {
+        return fLength;
+    }
+
+    /*
+     * @see dwtx.jface.text.ITextSelection#getStartLine()
+     */
+    public int getStartLine() {
+
+        try {
+            if (fDocument !is null)
+                return fDocument.getLineOfOffset(fOffset);
+        } catch (BadLocationException x) {
+        }
+
+        return -1;
+    }
+
+    /*
+     * @see dwtx.jface.text.ITextSelection#getEndLine()
+     */
+    public int getEndLine() {
+        try {
+            if (fDocument !is null) {
+                int endOffset= fOffset + fLength;
+                if (fLength !is 0)
+                    endOffset--;
+                return fDocument.getLineOfOffset(endOffset);
+            }
+        } catch (BadLocationException x) {
+        }
+
+        return -1;
+    }
+
+    /*
+     * @see dwtx.jface.text.ITextSelection#getText()
+     */
+    public String getText() {
+        try {
+            if (fDocument !is null)
+                return fDocument.get(fOffset, fLength);
+        } catch (BadLocationException x) {
+        }
+
+        return null;
+    }
+
+    /*
+     * @see java.lang.Object#equals(Object)
+     */
+    public bool equals(Object obj) {
+        if (obj is this)
+            return true;
+
+        if (obj is null || getClass() !is obj.getClass())
+            return false;
+
+        TextSelection s= (TextSelection) obj;
+        bool sameRange= (s.fOffset is fOffset && s.fLength is fLength);
+        if (sameRange) {
+
+            if (s.fDocument is null && fDocument is null)
+                return true;
+            if (s.fDocument is null || fDocument is null)
+                return false;
+
+            try {
+                String sContent= s.fDocument.get(fOffset, fLength);
+                String content= fDocument.get(fOffset, fLength);
+                return sContent.equals(content);
+            } catch (BadLocationException x) {
+            }
+        }
+
+        return false;
+    }
+
+    /*
+     * @see java.lang.Object#hashCode()
+     */
+    public int hashCode() {
+        int low= fDocument !is null ? fDocument.hashCode() : 0;
+        return (fOffset << 24) | (fLength << 16) | low;
+    }
+}
+