Changeset 16838 for gli/trunk/src/org/greenstone/gatherer/file/FileNode.java

Timestamp:

2008-08-15T18:37:16+12:00 (16 years ago)

Author:

ak19

Message:

Moved the displayString and toString() added recently in CollectionTreeNode into the superclass FileNode class, since WorkspaceTreeNode may also want to attempt to display filenames with proper encoding (if UTF8)

File:

• gli/trunk/src/org/greenstone/gatherer/file/FileNode.java (modified) (3 diffs)

gli/trunk/src/org/greenstone/gatherer/file/FileNode.java

@@ -20 +20 @@
     protected FileSystemModel model = null;
     protected MutableTreeNode parent = null;
+    /** The string that is displayed as the filename. Attempts to be in the correct encoding. */
+    protected String displayFileName = null;
 
 
@@ -32 +34 @@
         this.allows_children = false;
     }
-    }
-
+    displayFileName = calcDisplayString();
+    }
+
+
+     /** This method returns a string representation of the filenodes in the Collection
+     * Tree, that can then be displayed in the tree. 
+     * We'll initially assume that the filenames are utf8 encoded and so convert the
+     * filename into utf8 for proper presentation in the Collection tree pane.
+     * If the filenames are not utf8, then the conversion would have introduced funny
+     * characters. Therefore, when converting to utf8, if the converted filename 
+     * contains the special character '\ufffd', then we know the conversion did not work
+     * and we return the original string which may or may not be properly presented by
+     * default.
+     * See http://java.sun.com/j2se/1.4.2/docs/api/java/nio/charset/CharsetDecoder.html
+     * which says "How a decoding error is handled depends upon the action requested for 
+     * that type of error, which is described by an instance of the CodingErrorAction class.
+     * The possible error actions are to ignore the erroneous input, report the error to
+     * the invoker via the returned CoderResult object, or replace the erroneous input with
+     * the current value of the replacement string. The replacement has the initial value 
+     * "\uFFFD"; its value may be changed via the replaceWith method."
+     * The following made me think that String(byte[], String charsetName) constructor may
+     * use the replacement value \uFFFD.
+     * http://www.experts-exchange.com/Programming/Programming_Languages/Java/Q_20512969.html
+     * mentions the following which made me think of this: 
+     * convertedStr = convertedStr.replace('\ufffd', ' ');
+     */
+    protected String calcDisplayString() {
+    String filename = file.getName();
+    try{
+        String utf8filename = new String(filename.getBytes(), "UTF8");
+        if(utf8filename.indexOf('\ufffd') == -1) {
+        return utf8filename;
+        } else { // contains the character indicating that it's invalid utf8
+        // return the original string
+        return filename;
+        }
+    } catch(java.io.UnsupportedEncodingException e) {
+        return filename;
+    }
+    }
 
     /** Returns the children of the node as an Enumeration. */
@@ -312 +352 @@
     }
     else {
-        return file.getName();
+        if(displayFileName == null) {    
+        displayFileName = calcDisplayString();
+        }
+        return displayFileName;     
     }
     }