Changeset 3593

Timestamp:

2002-11-30T15:07:07+13:00 (21 years ago)

Author:

say1

Message:

more comments and error handling

Location:

trunk/gsdl3/src/java/org/greenstone/gsdl3/selfContained

Files:

• DocumentStream.java (modified) (4 diffs)
• FilesDocumentStream.java (modified) (6 diffs)
• GeneratedDocumentStream.java (modified) (1 diff)
• Increment.java (modified) (2 diffs)
• IncrementRange.java (modified) (4 diffs)
• QueryDocumentStream.java (modified) (13 diffs)

trunk/gsdl3/src/java/org/greenstone/gsdl3/selfContained/DocumentStream.java

@@ -23 +23 @@
 
 // other java classes
+import java.io.Serializable;
 
 
@@ -35 +36 @@
  * 
  */
-interface DocumentStream {
+public interface DocumentStream extends Cloneable, Serializable {
   
   /**
@@ -43 +44 @@
    * @return the next document
    */
-  public Document nextDocument() throws Exception;
+  public Document nextDocument();
   /**
    * Is there a next document?
@@ -50 +51 @@
    * @return true if there is a next document
    */
-  public boolean hasNextDocument() throws Exception;
+  public boolean hasNextDocument();
   
 }

trunk/gsdl3/src/java/org/greenstone/gsdl3/selfContained/FilesDocumentStream.java

@@ -41 +41 @@
  * @see DocumentStream
  */
-class DocumentStreamFromFiles implements DocumentStream {
+public class FilesDocumentStream 
+  implements DocumentStream {
   /** the files we've found so far */
   Vector files = new Vector();
@@ -53 +54 @@
    * @param filename the filename of the file or directory
    */
-  public DocumentStreamFromFiles(String filename) throws IOException {
+  public FilesDocumentStream(String filename)  {
     File file = new File(filename);
     if (file.exists() && file.isDirectory())
@@ -66 +67 @@
    * @param file a handle to the file
    */
-  public DocumentStreamFromFiles(File file) {
+  public FilesDocumentStream(File file) {
     if (file.exists() && file.isDirectory())
       directories.add(file);
@@ -78 +79 @@
    * @exception java.io.IOException when the underlying file access does
    */
-  protected void expandIfNecessary() throws IOException {
+  protected void expandIfNecessary() {
     while (files.size() < 1 || directories.size() > 1) {
       File file = (File) directories.elementAt(directories.size() - 1);
       directories.removeElementAt(directories.size() - 1);
-      if (!file.exists()) throw new IOException ("error in expand: expecting a directory");
+      if (!file.exists()) throw new Error ("error in expand: expecting a directory");
       File[] fileArray = file.listFiles();
       for (int i=0;i<fileArray.length;i++){
@@ -99 +100 @@
    * @return the next document
    */
-  public Document nextDocument() throws Exception {
-    if (!hasNextDocument()) throw new Error("Doesn't have another Document");
-    File file = (File) files.elementAt(files.size() - 1);
-    files.removeElementAt(files.size() - 1);
-      
-    Reader reader = new FileReader(file);
-    InputSource xml_source = new InputSource(reader);
-          
-    XMLUtil.getDOMParser().parse(xml_source);
-    Document doc = XMLUtil.getDOMParser().getDocument();
-      
-    return doc;
+  public Document nextDocument() {
+    try {
+      if (!hasNextDocument()) throw new Error("Doesn't have another Document");
+      File file = (File) files.elementAt(files.size() - 1);
+      files.removeElementAt(files.size() - 1);
+       
+      Reader reader = new FileReader(file);
+      InputSource xml_source = new InputSource(reader);
+       
+      XMLUtil.getDOMParser().parse(xml_source);
+      Document doc = XMLUtil.getDOMParser().getDocument();
+       
+      return doc;
+    } catch (org.xml.sax.SAXException s) {
+      System.err.println("SAXException in nextDocument()");
+      throw new Error(s.toString());
+    } catch (IOException e) {
+      System.err.println("IOException in nextDocument()");
+      throw new Error(e.toString());
+    }
   }
     
@@ -120 +129 @@
    */
 
-  public boolean hasNextDocument() throws IOException {
+  public boolean hasNextDocument()  {
     expandIfNecessary();
     return (files.size() > 1);

trunk/gsdl3/src/java/org/greenstone/gsdl3/selfContained/GeneratedDocumentStream.java

@@ -95 +95 @@
    * @see org.w3c.dom.Document
    */
-  public Document nextDocument() throws Exception {
+  public Document nextDocument() {
 
 

trunk/gsdl3/src/java/org/greenstone/gsdl3/selfContained/Increment.java

@@ -46 +46 @@
    * @see Increment
    */
-  abstract String incrementString(String str) throws Exception;
+  abstract String incrementString(String str);
 
   /**
@@ -56 +56 @@
    * @see Increment
    */
-  abstract long incrementStream(Reader rdr, Writer wtr) throws Exception;
+  abstract long incrementStream(Reader rdr, Writer wtr);
 
   /**

trunk/gsdl3/src/java/org/greenstone/gsdl3/selfContained/IncrementRange.java

@@ -42 +42 @@
   implements Cloneable, Serializable
 {
- /**
+  /**
    * Create an IncrementRange which counts between first and last inclusive
    * 
@@ -83 +83 @@
    * Increment a stream of characters, reading from the reader and writing the incremented characters to the writer
    * 
-   * @exception java.io.Exception if any of the characters in the string are outside the range of first-last
+   * @exception java.io.Error if any of the characters in the string are outside the range of first-last
    * @param str the string to be incremented
    * @return the incremented string
    * @see Increment
    */
-  long incrementStream(Reader rdr, Writer wtr)
-    throws Exception {
-    long count = 0; // the return value
+  long incrementStream(Reader rdr, Writer wtr) {
+    try {
+      long count = 0; // the return value
     
-    int i = rdr.read();
-    boolean carry = true;
+      int i = rdr.read();
+      boolean carry = true;
     
-    while (i != -1) {
-      char c = (char) i;
+      while (i != -1) {
+    char c = (char) i;
       
-      // check the validity of the character we're about to increment
-      if (c < first || c > last) 
-    throw new Exception("Character '" + c + "' is ouside range");
+    // check the validity of the character we're about to increment
+    if (c < first || c > last) 
+      throw new Error("Character '" + c + "' is ouside range");
       
-      if (c == last) {
-    if (carry == true) {
-      wtr.write(first);
-      carry = true;
+    if (c == last) {
+      if (carry == true) {
+        wtr.write(first);
+        carry = true;
+      } else {
+        wtr.write(c);
+        carry = false;
+      }
     } else {
-      wtr.write(c);
-      carry = false;
+      if (carry == true) {
+        wtr.write(++c);
+        carry = false;
+      } else {
+        wtr.write(c);
+        carry = false;
+      } 
     }
-      } else {
-    if (carry == true) {
-      wtr.write(++c);
-      carry = false;
-    } else {
-      wtr.write(c);
-      carry = false;
-    } 
-      }
-      count++;
-
-      // read the next character
-      i = rdr.read();
-    }
-    if (carry == true) {
-      wtr.write(first);
-      count++;
-    }
-    return count;
+    count++;
+
+    // read the next character
+    i = rdr.read();
+      }
+      if (carry == true) {
+    wtr.write(first);
+    count++;
+      }
+      return count;
+    } catch (IOException e) {
+      System.err.println("IOException in incrementStream()");
+      throw new Error(e.toString());
+    }
   }
 
@@ -134 +138 @@
    * Increment a string of characters
    * 
-   * @exception java.io.Exception if any of the characters in the string are outside the range of first-last
+   * @exception java.lang.Error if any of the characters in the string are outside the range of first-last
    * @param str the string to be incremented
    * @return the incremented string
    * @see Increment
    */
-  public final String incrementString(String str) 
-    throws Exception {
+  public final String incrementString(String str)  {
     StringBuffer buffer = new StringBuffer();
     if (str == "") {
@@ -150 +153 @@
     char c = str.charAt(i);
     if (c < first || c > last) 
-      throw new Exception("Character '" + c + "' is ouside range");
+      throw new Error("Character '" + c + "' is ouside range");
 
     if (c == last) {

trunk/gsdl3/src/java/org/greenstone/gsdl3/selfContained/QueryDocumentStream.java

@@ -1 +1 @@
 /*
- *    QueryDocumentStream.java.java
+ *    QueryDocumentStream.java
  *    Copyright (C) 2002 New Zealand Digital Library, http://www.nzdl.org
  *
@@ -25 +25 @@
 import javax.xml.transform.TransformerException;
 import javax.xml.transform.TransformerFactory;
-import javax.xml.transform.Result;
-import javax.xml.transform.Source;
 import javax.xml.transform.dom.DOMResult;
 import javax.xml.transform.dom.DOMSource;
 import javax.xml.transform.stream.StreamResult;
 import javax.xml.transform.stream.StreamSource;
-import org.apache.xalan.xslt.*;
-import org.apache.xerces.dom.DocumentImpl;
-import org.apache.xerces.dom.ElementImpl;
-import org.apache.xerces.dom.TextImpl;
 import org.w3c.dom.Document;
-import org.w3c.dom.Node;
-import org.w3c.dom.NodeList;
 
 // other java classes
@@ -44 +36 @@
 /**
  * QueryDocumentStream takes another document stream and removes 
- * from the stream all documents which fail to match a XSLT query
- *
+ * from the stream all documents which fail to match a XSLT query.
+ * The default query returns only those documents containing the 
+ * string "the".
  *
  * @author <a href="http://www.cs.waikato.ac.nz/~say1/">stuart yeates</a> (<a href="mailto:[email protected]">s
@@ -67 +60 @@
     "   </xsl:template>" +
     "</xsl:stylesheet>";
-
+  /** The first part of the default quesy for a string other than "the" */
   public static final String DEFAULT_QUERY_STRING_1_1 =   
     "<xsl:stylesheet version=\"1.0\" " +
@@ -76 +69 @@
     "      <xsl:if test=\"contains(.,'";
 
+  /** The second part of the default quesy for a string other than "the" */
   public static final String DEFAULT_QUERY_STRING_1_2 =   
     "')\">" +
@@ -84 +78 @@
 
 
-  /** The next string */
+  /** The query */
   protected StreamSource query = new StreamSource(new StringReader(DEFAULT_QUERY_STRING));
 
@@ -92 +86 @@
   /** A cached Document */
   protected Document cached = null;
+
+  /** The transformer factory */
   TransformerFactory transformerFactory  = null;
-    Transformer transformer  = null;
+
+  /** The transformer */
+  Transformer transformer  = null;
 
   /** Uses the default query (looking for the) over the default DocumentStream (all ascii strings) */
@@ -161 +159 @@
     }
   }
-  
-
-  
-  
   /**
    * Generates the nest document in the sequence
@@ -172 +166 @@
    * @see org.w3c.dom.Document
    */
-  public Document nextDocument() throws Exception {
+  public Document nextDocument()  {
 
     if (hasNextDocument() == false)
-      throw new Exception("no more docs");
+      throw new Error("no more docs");
     Document result = cached;
     cached = null;
@@ -185 +179 @@
    * @return true if there are more docs
    */
-  public boolean hasNextDocument() throws Exception {
-    lookInStream()
-      return (cached != null);
+  public boolean hasNextDocument() {
+    lookInStream();
+    return (cached != null);
   }
   /**
@@ -199 +193 @@
    * @see blank
    */
-  protected boolean lookInStream() throws Exception {
+  protected boolean lookInStream()  {
 
     while (stream.hasNextDocument() && cached == null) {
@@ -210 +204 @@
       try {
     
-      transformer.transform(input, output);
-      
-      // if the transformed document is not empty don't cache it
-      if (output.getNode().getFirstChild() != null)
-    cached = (Document) output.getNode();
-      
+    transformer.transform(input, output);
+      
+    // if the transformed document is not empty don't cache it
+    if (output.getNode().getFirstChild() != null)
+      cached = (Document) output.getNode();
+      
+      } catch (TransformerConfigurationException e) {
+    System.err.println("XMLTransformer: couldn't create transformer object: "+e.getMessage());
       } catch (TransformerException e) {
     System.err.println("XMLTransformer: couldn't transform the source: " + e.getMessage());
@@ -228 +224 @@
       if (false) { // debugging info
     
-    StreamResult result = new StreamResult(System.out);
-    TransformerFactory transformerFactory = TransformerFactory.newInstance();
-    Transformer transformer = transformerFactory.newTransformer();
-    
-    Source source = new DOMSource(candidate);
-    transformer.transform(source,result);
-    
-    System.out.print(" ==> ");
-    
-    if (cached != null) {
-      Source source2 = new DOMSource(cached);
-      transformer.transform(source2,result);
-    } 
-    System.out.println();
-    System.out.println("======================================================");
+    try {
+      StreamResult result = new StreamResult(System.out);
+      Transformer transformer = transformerFactory.newTransformer();
+      
+      Source source = new DOMSource(candidate);
+      transformer.transform(source,result);
+      
+      System.out.print(" ==> ");
+      
+      if (cached != null) {
+        Source source2 = new DOMSource(cached);
+        transformer.transform(source2,result);
+      } 
+      System.out.println();
+      System.out.println("======================================================");
+      
+    } catch (TransformerConfigurationException e) {
+      System.err.println("XMLTransformer: couldn't create transformer object: "+e.getMessage());
+    } catch (TransformerException e) {
+      System.err.println("XMLTransformer: couldn't transform the source: " + e.getMessage());
+      cached = null;
+      return false;
+    } catch (Exception e) {
+      System.err.println("Exception: " + e.getMessage());
+      cached = null;
+      return false;
+    }
     
       }
     }
-    return cached == null;
-    
+    return cached == null;    
   }