Changeset 5944 for trunk/gsdl3/src/java/org/greenstone/gsdl3/gs3build/doctypes/DocumentList.java

Timestamp:

2003-11-24T14:26:35+13:00 (20 years ago)

Author:

cs025

Message:

Index document type, metadata extensions

File:

• trunk/gsdl3/src/java/org/greenstone/gsdl3/gs3build/doctypes/DocumentList.java (modified) (2 diffs)

trunk/gsdl3/src/java/org/greenstone/gsdl3/gs3build/doctypes/DocumentList.java

@@ -1 +1 @@
 package org.greenstone.gsdl3.gs3build.doctypes;
 
+import java.util.Iterator;
 import java.util.List;
 import java.util.ArrayList;
@@ -9 +10 @@
 import java.io.IOException;
 
+import java.net.URL;
+
+import java.sql.SQLException;
+import java.sql.ResultSet;
+
 import org.greenstone.gsdl3.gs3build.util.GS3SQLConnection;
+import org.greenstone.gsdl3.gs3build.database.GS3SQLSelect;
+import org.greenstone.gsdl3.gs3build.database.GS3SQLWhereItem;
+import org.greenstone.gsdl3.gs3build.database.GS3SQLWhere;
+import org.greenstone.gsdl3.gs3build.database.GS3SQLField;
 
 public class DocumentList
 {
-    DocumentInterface []       list;
-    int                        size;
-    int                        used;
-    DocumentIDFactoryInterface idFactory;
+  DocumentInterface []       list;       // what is currently cached
+  int                        size;       // the maximum number in the cache
+  int                        used;       // the actual number in the cache
+  int                        count;      // the total number of known documents
+  DocumentIDFactoryInterface idFactory;  // A manufacturer of novel document IDs
+  GS3SQLConnection           connection; // used to query the SQL database
+
+  private static final int maxSize = 10;
+
+  public DocumentList(GS3SQLConnection connection)
+  { this.idFactory = null;
+    this.list  = new DocumentInterface[10];
+    this.used  = 0;
+    this.size  = 10;
+    this.count = 0;
+    this.connection = connection;
+  }
+
+  public DocumentList(DocumentIDFactoryInterface idFactory, GS3SQLConnection connection)
+  { this.idFactory = idFactory;
+    this.list  = new DocumentInterface[10];
+    this.used  = 0;
+    this.size  = 10;
+    this.count = 0;
+    this.connection = connection;
+  }
+
+  /**
+   *  Write the document into the document list (cache) and the database.
+   *
+   *  @param <code>DocumentInterface</code> the document itself
+   */
+  public void addDocument(DocumentInterface document)
+  { // increase cache size, etc. as necessary
+    if (this.used == this.size) {
+      if (this.size >= maxSize) {
+    for (int i = 0; i < this.size - 1; i ++) {
+      this.list[i] = this.list[i+1];
+    }
+    this.used --;
+      }
+      else {
+    this.ensureSize((this.size * 2) > maxSize ? maxSize : (this.size * 2));
+      }
+    }
+    
+    // insert the document itself
+    this.list[this.used] = document;
+
+    // set the document identifier, if not already set
+    if (document.getID() == null) {
+      DocumentID id = this.idFactory.getNewDocumentID(document);
+      document.setID(id);
+    }
+
+    // add to the database as well
+    document.getSQLWriter().writeDocument(document, this.connection);
+
+    // Remember that we've used one more item from the cache.
+    this.used ++;
+
+    // Note additional document
+    this.count ++;
+  }
+
+  /**
+   *  Note that an individual document is modified, and act accordingly
+   *
+   *  @param <code>DocumentInterface</code> the document
+   */
+  public void modifiedDocument(DocumentInterface document)
+  { document.getSQLWriter().writeDocument(document, this.connection);
+  }
+
+  /**
+   *  Get an iterator across all the documents, not merely those in
+   *  the cache.  Note that this <code>Iterator</code> does <b>not</b>
+   *  support the <code>remove()</code> function, and will raise an
+   *  <code>UnsupportedOperationException</code> if you attempt to do
+   *  so.
+   *
+   *  @return <code>Iterator</code> the iterator across the documents.
+   */
+  public Iterator iterator()
+  { return new DocumentListIterator(connection);
+  }
+
+  /**
+   *  Get the nth member of the <b>cached</b> document list.
+   *
+   *  @deprecated
+   */
+  public DocumentInterface getDocument(int index)
+  { if (index < 0 || index >= this.used)
+    { return null;
+    }
+    return this.list[index];
+  }
+
+  /**
+  public DocumentID getDocumentID(int index)
+  { if (index < 0 || index >= this.used)
+    { return null;
+    }
+    return this.list[index].getID();
+  }
+  */
+
+  protected void ensureSize(int size)
+  { DocumentInterface [] newList = new DocumentInterface[size];
+    System.arraycopy(this.list, 0, newList, 0, this.size);
+    this.list = newList;
+    this.size = size;
+  }
+
+  public void writeDocuments(File directory)
+  { Iterator documents = this.iterator();
+    int item = 0;
+
+    while (documents.hasNext())
+    { DocumentInterface document = (DocumentInterface) documents.next();
+      try
+      { item ++;
+    File localFile = new File(directory, "Doc"+Integer.toString(item)+".xml");
+    FileWriter fileWriter = new FileWriter(localFile);
+    PrintWriter writer = new PrintWriter(fileWriter);
+    document.getMETSWriter().writeDocument(document, writer);
+    writer.close();
+    fileWriter.close();
+      }
+      catch (IOException io)
+      { 
+      }
+    }
+  }
+
+  public void writeSQLDocuments(GS3SQLConnection connection)
+  { for (int i = 0; i < this.used; i ++)
+    { this.list[i].getSQLWriter().writeDocument(this.list[i], connection);
+    }
+  }
+
+  public static DocumentList readSQLDocuments(GS3SQLConnection connection)
+  { DocumentList list = new DocumentList(connection);
+
+    GS3SQLSelect select = new GS3SQLSelect("document");
+    select.addField("*");
+    
+    ResultSet documents;
+    try {
+      connection.execute(select.toString());
+      documents = connection.getResultSet();
+
+      if (documents.first())
+      { do
+    { DocumentInterface document = AbstractDocument.readSQL(connection, documents);
+          list.addDocument(document);
+    }
+    while (documents.next());
+      }
+    }
+    catch (java.sql.SQLException ex)
+    { System.out.println(ex);
+      return null;
+    }
+
+    return list;
+  }
+
+  public int getCount()
+  { return this.count;
+  }
+
+  public int size()
+  { return this.used;
+  }
+}
+
+class DocumentListIterator implements Iterator
+{
+  private boolean hasNext;
+  private ResultSet resultSet;
+  private GS3SQLConnection connection;
+
+  public DocumentListIterator(GS3SQLConnection connection)
+  {
+    this.connection = connection;
+
+    GS3SQLSelect select = new GS3SQLSelect("document");
+    select.addField("*");
+
+    try {
+      connection.execute(select.toString());
+      this.resultSet = connection.getResultSet();
+      this.hasNext = this.resultSet.first();
+    } catch (SQLException ex) {
+      this.hasNext = false;
+    }
+  }
+
+  public boolean hasNext()
+  { return this.hasNext;
+  }
+
+  public Object next()
+  {
+    // get the 'next' document first
+    DocumentInterface document = AbstractDocument.readSQL(connection, this.resultSet);
+
+    // now actually step forward to the next item, so that we know if we have one!
+    try {
+      this.hasNext = this.resultSet.next();
+
+      if (!this.hasNext) {
+    this.resultSet.close(); // be a good citizen & close used result sets
+      }
+    } catch (SQLException ex) {
+      this.hasNext = false;
+    }
+    return document;
+  }
+  
+  public void remove() throws UnsupportedOperationException
+  { throw new UnsupportedOperationException("DocumentList does not support iterator removal of documents");
+  }
+
+  public List getDocumentIdsWithFile(URL fileLocation)
+  { List reply = new ArrayList();
+
+    GS3SQLSelect select = new GS3SQLSelect("files");
+    select.addField("*");
+    GS3SQLWhere  where  = new GS3SQLWhere(new GS3SQLWhereItem("FileLocation", "=", fileLocation.toString()));
+    select.setWhere(where);
+
+    this.connection.execute(select.toString());
+
+    ResultSet results = this.connection.getResultSet();
+    if (results != null) {
+      select = new GS3SQLSelect("filegroups");
+      select.addField("DocID");
+      select.setDistinct(true);
+      
+      where = new GS3SQLWhere();
+      where.setCondition(GS3SQLWhere.OR_CONDITION);
+
+      GS3SQLWhereItem whereItem = null;
+
+      try {
+    results.first();
+    do {
+      int fileGroupRef = results.getInt("FileGroupRef");
+      whereItem = new GS3SQLWhereItem("FileGroupRef", "=", Integer.toString(fileGroupRef), GS3SQLField.INTEGER_TYPE);
+      where.add(whereItem);
+    }
+    while (results.next());
+    select.setWhere(where);
+    results.close();
     
-    public DocumentList(DocumentIDFactoryInterface idFactory)
-    {   this.idFactory = idFactory;
-        this.list = new DocumentInterface[10];
-        this.used = 0;
-        this.size = 10;
-    }
-
-    public void addDocument(DocumentInterface document)
-    {   if (this.used == this.size) {
-            this.ensureSize(this.size * 2);
-        }
-        this.list[this.used] = document;
-        DocumentID id = this.idFactory.getNewDocumentID(document);
-        document.setID(id);
-        this.used ++;
-    }
-
-    public DocumentInterface getDocument(int index)
-    {   if (index < 0 || index >= this.used)
-        {   return null;
-        }
-        return this.list[index];
-    }
-
-    public DocumentID getDocumentID(int index)
-    {   if (index < 0 || index >= this.used)
-        {   return null;
-        }
-        return this.list[index].getID();
-    }
-
-    public void ensureSize(int size)
-    {   DocumentInterface [] newList = new DocumentInterface[size];
-        System.arraycopy(this.list, 0, newList, 0, this.size);
-        this.list = newList;
-        this.size = size;
-    }
-
-    public void writeDocuments(File directory)
-    {   for (int i = 0; i < this.used; i ++)
-        {   try
-            {
-                File localFile = new File(directory, "Doc"+Integer.toString(i)+".xml");
-                FileWriter fileWriter = new FileWriter(localFile);
-                PrintWriter writer = new PrintWriter(fileWriter);
-                this.list[i].getMETSWriter().writeDocument(this.list[i], writer);
-                writer.close();
-                fileWriter.close();
-            }
-            catch (IOException io)
-            {   
-            }
-        }
-    }
-
-    public void writeSQLDocuments(GS3SQLConnection connection)
-    {   for (int i = 0; i < this.used; i ++)
-        {   this.list[i].getSQLWriter().writeDocument(this.list[i], connection);
-        }
-    }
-
-    public int size()
-    {   return this.used;
-    }
+    this.connection.execute(select.toString());
+    
+    results = this.connection.getResultSet();
+    results.first();
+    do {
+      String docId = results.getString("DocID");
+      reply.add(docId);
+    } while (results.next());
+      } 
+      catch (SQLException sqlEx)
+      { System.err.println(sqlEx);
+      }
+    }
+    return reply;
+  }
 }