first commit

CS2335/lab5/src/nettext/file/DocumentListWriter.java

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+package nettext.file;
+
+import java.io.PrintWriter;
+import java.io.IOException;
+import java.io.FileOutputStream;
+
+import nettext.document.Document;
+import nettext.document.DocumentList;
+import nettext.document.DocumentListIterator;
+
+/**
+ * Writer for the available list of Documents
+ */
+public class DocumentListWriter {
+  /**
+   * The Writer.
+   */
+  private PrintWriter oStream;
+
+  /**
+   * The Writee.
+   */
+  private String fileName;
+
+  /**
+   * Standard Initialization function that initializes all fields
+   * to default values
+   *@param fileN afilename
+   *@return boolean
+   */
+  public boolean initialize(String fileN) {
+    if (fileN == null) {
+      return false;
+    }
+
+    this.fileName = fileN;
+
+    //initialize the PrintWriter
+    try {
+      oStream = new PrintWriter(new FileOutputStream(fileName));
+    } catch (IOException ioe) {
+      System.err.println("Error initializing list writer:");
+      System.err.println("\t" + ioe.getMessage());
+      System.err.flush();
+      return false;
+    }
+
+    return true;
+  }
+
+  /**
+   * Flush/Close Buffers/Streams
+   */
+  public void cleanUp() {
+    oStream.flush();
+    oStream.close();
+
+    oStream = null;
+  }
+
+  /**
+   * Writes the document list if possible.
+   *
+   * @param list a <code>DocumentList</code> value
+   * @return a <code>boolean</code> value
+   */
+  public boolean writeDocumentList(final DocumentList list) {
+    DocumentListIterator dli = list.getIterator();
+
+    if (oStream == null) {
+      return false;
+    }
+
+    //Start file
+    if (!startFile()) { return false; }
+
+    //Start list
+    if (!startList(list)) { return false; }
+
+    //Write documents
+    while (dli.hasNext()) {
+      if (!writeDocument(dli.next())) { return false; }
+    }
+
+    //End list
+    if (!endList()) { return false; }
+
+    //End file
+    if (!endFile()) { return false; }
+
+    return true;
+  }
+
+  /**
+   * Write the things at the start of the File
+   *@return boolean
+   */
+  public boolean startFile() {
+    try {
+      //Print out the start of the document.
+      this.writeOut("<?xml version='1.0'?>");
+      this.nl();
+      this.nl();
+    } catch (IOException ioe) {
+      System.err.println("IO EXCEPTION!!! BAD!!!!, startFile()-NTOH");
+      return false;
+    }
+
+    return true;
+  }
+
+  /**
+   * Write out the things related to ending the file
+   * @return a <code>boolean</code> value
+   */
+  public boolean endFile() {
+    return true;
+  }
+
+  /**
+   * Writes the start of the document list into the file.
+   *
+   * @param list a <code>DocumentList</code> value
+   * @return a <code>boolean</code> value
+   */
+  public boolean startList(final DocumentList list) {
+    try {
+      this.writeOut("<" + XMLSettings.DOCUMENT_LIST);
+      this.writeOut(" numDocuments=\"" + list.size() + "\"");
+      this.writeOut(">");
+      this.nl();
+    } catch (IOException ioe) {
+      System.err.println("IO Exception!! startList() - NTOH");
+      return false;
+    }
+
+    return true;
+  }
+
+  /**
+   * Writes out the end of the document list into the file.
+   *
+   * @return a <code>boolean</code> value
+   */
+  public boolean endList() {
+    try {
+      this.writeOut("</" + XMLSettings.DOCUMENT_LIST + ">");
+      this.nl();
+    } catch (IOException ioe) {
+      System.err.println("IO Exception!! endList() - NTOH");
+      return false;
+    }
+
+    return true;
+  }
+
+  /**
+   * Write out the document.
+   * @param toWrite a <code>Document</code> value
+   * @return a <code>boolean</code> value
+   */
+  public boolean writeDocument(Document toWrite) {
+    try {
+      //  Figure out the writeOut (the docName shouldn't be fileName!)
+      this.writeOut("\t<"
+                    + XMLSettings.DOCUMENT_KEY
+                    + " name=\""
+                    + toWrite.getDocumentName()
+                    + "\" id=\""
+                    + toWrite.getDocumentId()
+                    + "\" />");
+      this.nl();
+    } catch (IOException ioe) {
+      System.err.println("IO Exception!! startDocument() - NTOH");
+      return false;
+    }
+
+    return true;
+  }
+
+  /**
+   * Helper function
+   * Writes the String toWrite to the stdOut
+   *@param toWrite toWrite
+   *@throws IOException exception
+   */
+  private void writeOut(String toWrite) throws IOException {
+    oStream.print(toWrite);
+    oStream.flush();
+  }
+
+  /**
+   * Helper function
+   *   Writes a newline to the file
+   *@throws IOException exception
+   */
+  private void nl() throws IOException {
+    //flush once for the bulk, twice for the left-overs
+    oStream.print("\n");
+    oStream.flush();
+  }
+
+}