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From rhille...@apache.org
Subject svn commit: r1490799 - in /db/derby/code/trunk: java/engine/org/apache/derby/vti/XmlVTI.java tools/jar/extraDBMSclasses.properties
Date Fri, 07 Jun 2013 19:44:14 GMT
Author: rhillegas
Date: Fri Jun  7 19:44:14 2013
New Revision: 1490799

URL: http://svn.apache.org/r1490799
Log:
DERBY-6256: Commit derby-6256-01-aa-move-XmlVTI-into-product.diff, moving the XmlVTI into
the vti package of the product.

Added:
    db/derby/code/trunk/java/engine/org/apache/derby/vti/XmlVTI.java   (with props)
Modified:
    db/derby/code/trunk/tools/jar/extraDBMSclasses.properties

Added: db/derby/code/trunk/java/engine/org/apache/derby/vti/XmlVTI.java
URL: http://svn.apache.org/viewvc/db/derby/code/trunk/java/engine/org/apache/derby/vti/XmlVTI.java?rev=1490799&view=auto
==============================================================================
--- db/derby/code/trunk/java/engine/org/apache/derby/vti/XmlVTI.java (added)
+++ db/derby/code/trunk/java/engine/org/apache/derby/vti/XmlVTI.java Fri Jun  7 19:44:14 2013
@@ -0,0 +1,286 @@
+/*
+
+Derby - Class org.apache.derby.vti.XmlVTI
+
+Licensed to the Apache Software Foundation (ASF) under one or more
+contributor license agreements.  See the NOTICE file distributed with
+this work for additional information regarding copyright ownership.
+The ASF licenses this file to You under the Apache License, Version 2.0
+(the "License"); you may not use this file except in compliance with
+the License.  You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+*/
+
+package org.apache.derby.vti;
+
+import java.io.*;
+import java.lang.reflect.*;
+import java.net.URL;
+import java.sql.*;
+import java.text.DateFormat;
+import java.text.ParseException;
+import javax.xml.parsers.*;
+import org.w3c.dom.*;
+
+/**
+ * <p>
+ * This is a VTI designed to read XML files which are structured like row sets.
+ * This VTI takes the following arguments:
+ * </p>
+ *
+ * <ul>
+ * <li>xmlResourceName - An URL identifying an xml resource.</li>
+ * <li>rowTag - The tag of the element which contains the row-structured content.</li>
+ * <li>childTags - The attributes and descendant elements inside the row element which
should be treated as columns.</li>
+ * </ul>
+ *
+ * <p>
+ * Here is a sample declaration:
+ * </p>
+ *
+ * <pre>
+ * create function findbugs( xmlResourceName varchar( 32672 ), rowTag varchar( 32672 ), childTags
varchar( 32672 )... )
+ * returns table
+ * (
+ *      className   varchar( 32672 ),
+ *      bugCount    int
+ * )
+ * language java parameter style derby_jdbc_result_set no sql
+ * external name 'org.apache.derby.vti.XmlVTI.xmlVTI';
+ * </pre>
+ *
+ * <p>
+ * ...and here is a sample invocation:
+ * </p>
+ *
+ * <pre>
+ * create view findbugs as
+ * select *
+ * from table
+ * (
+ *      findbugs
+ *      (
+ *          'file:///Users/me/static-analysis/findbugs.xml',
+ *          'ClassStats',
+ *          'class', 'bugs'
+ *      )
+ *  ) v;
+ * 
+ * select * from findbugs where bugCount != 0;
+ * </pre>
+ */
+public  class   XmlVTI  extends StringColumnVTI
+{
+    ///////////////////////////////////////////////////////////////////////////////////
+    //
+    // CONSTANTS
+    //
+    ///////////////////////////////////////////////////////////////////////////////////
+
+    ///////////////////////////////////////////////////////////////////////////////////
+    //
+    // STATE
+    //
+    ///////////////////////////////////////////////////////////////////////////////////
+
+    private String      _rowTag;
+    private String      _xmlResourceName;
+
+    private int             _rowIdx = -1;
+    private int             _rowCount = -1;
+    private String[]    _currentRow;
+    
+    private DocumentBuilder _builder;
+    private NodeList    _rawRows;
+
+    ///////////////////////////////////////////////////////////////////////////////////
+    //
+    // CONSTRUCTORS
+    //
+    ///////////////////////////////////////////////////////////////////////////////////
+
+    /**
+     * <p>
+     * Build a XmlVTI given the name of an xml resource, the  tag of the row
+     * element, and an array of attribute-names/element-tags underneath the row element
+     * </p>
+     */
+    public  XmlVTI( String xmlResourceName, String rowTag, String... childTags )
+    {
+        super( childTags );
+
+        _xmlResourceName = xmlResourceName;
+        _rowTag = rowTag;
+    }
+    
+    ///////////////////////////////////////////////////////////////////////////////////
+    //
+    // ENTRY POINT (SQL FUNCTION)
+    //
+    ///////////////////////////////////////////////////////////////////////////////////
+
+    /** This is the static method bound to the function */
+    public  static  XmlVTI  xmlVTI( String xmlResourceName, String rowTag, String... childTags
)
+    {
+        return new XmlVTI( xmlResourceName, rowTag, childTags );
+    }
+    
+    ///////////////////////////////////////////////////////////////////////////////////
+    //
+    // StringColumnVTI BEHAVIOR TO BE IMPLEMENTED BY SUBCLASSES
+    //
+    ///////////////////////////////////////////////////////////////////////////////////
+
+    /**
+     * <p>
+     * Get the string value of the column in the current row identified by the 1-based columnNumber.
+     * </p>
+     */
+    protected  String  getRawColumn( int columnNumber ) throws SQLException
+    {
+        try {
+            return  _currentRow[ columnNumber - 1 ];
+        } catch (Throwable t) { throw new SQLException( t.getMessage() ); }
+    }
+    
+    ///////////////////////////////////////////////////////////////////////////////////
+    //
+    // ResultSet BEHAVIOR
+    //
+    ///////////////////////////////////////////////////////////////////////////////////
+
+    public  void close() throws SQLException
+    {
+        _builder = null;
+        _rawRows = null;
+    }
+
+    public  ResultSetMetaData   getMetaData() throws SQLException
+    {
+        throw new SQLException( "Not implemented." );
+    }
+    
+    public  boolean next() throws SQLException
+    {
+        try {
+            if ( _rowIdx < 0 ) { readRows(); }
+
+            if ( ++_rowIdx < _rowCount )
+            {
+                parseRow( _rowIdx );
+                return true;
+            }
+            else { return false; }
+        } catch (Throwable t)
+        {
+            t.printStackTrace( System.out );
+            throw new SQLException( t.getMessage() );
+        }
+    }
+
+    ///////////////////////////////////////////////////////////////////////////////////
+    //
+    // MINIONS
+    //
+    ///////////////////////////////////////////////////////////////////////////////////
+
+    //////////////////////////
+    //
+    // XML MINIONS
+    //
+    //////////////////////////
+
+    /**
+     * <p>
+     * Fault in the list of rows.
+     * </p>
+     */
+     private    void    readRows() throws Exception
+    {
+        DocumentBuilderFactory  factory = DocumentBuilderFactory.newInstance();
+        
+        _builder = factory.newDocumentBuilder();
+
+        URL                 url = new URL( _xmlResourceName );
+        InputStream     is = url.openStream();
+        Document        doc = _builder.parse( is );
+        Element             root = doc.getDocumentElement();
+
+        _rawRows = root.getElementsByTagName( _rowTag );
+        _rowCount = _rawRows.getLength();
+
+        is.close();
+    }
+    
+    /**
+     * <p>
+     * Parse a row into columns.
+     * </p>
+     */
+     private    void    parseRow( int rowNumber ) throws Exception
+    {
+        Element         rawRow = (Element) _rawRows.item( rowNumber );
+        int                 columnCount = getColumnCount();
+        
+        _currentRow = new String[ columnCount ];
+
+        for ( int i = 0; i < columnCount; i++ )
+        {
+            // first look for an attribute by the column name
+            String      columnName = getColumnName( i + 1 );
+            String      contents = rawRow.getAttribute( columnName );
+
+            // if there is not attribute by that name, then look for descendent elements
by
+            // that name. concatenate them all.
+            if ( (contents == null) ||  "".equals( contents ) )
+            {
+                NodeList    children = rawRow.getElementsByTagName( columnName );
+
+                if ( (children != null) && (children.getLength() > 0) )
+                {
+                    int                 childCount = children.getLength();
+                    StringBuffer    buffer = new StringBuffer();
+
+                    for ( int j = 0; j < childCount; j++ )
+                    {
+                        Element     child = (Element) children.item( j );
+                        // separate values with spaces.
+                        if (j != 0)
+                            buffer.append(" ");
+                        buffer.append( squeezeText( child ) );
+                    }
+                    contents = buffer.toString();
+                }
+            }
+
+            _currentRow[ i ] = contents;
+        }
+    }
+    
+    /**
+     * <p>
+     * Squeeze the text out of an Element.
+     * </p>
+     */
+    private String squeezeText( Element node )
+        throws Exception
+    {
+        String      text = null;
+        Node        textChild = node.getFirstChild();
+
+        if ( textChild != null ) { text = textChild.getNodeValue(); }
+
+        return text;
+    }
+
+
+}
+

Propchange: db/derby/code/trunk/java/engine/org/apache/derby/vti/XmlVTI.java
------------------------------------------------------------------------------
    svn:eol-style = native

Modified: db/derby/code/trunk/tools/jar/extraDBMSclasses.properties
URL: http://svn.apache.org/viewvc/db/derby/code/trunk/tools/jar/extraDBMSclasses.properties?rev=1490799&r1=1490798&r2=1490799&view=diff
==============================================================================
--- db/derby/code/trunk/tools/jar/extraDBMSclasses.properties (original)
+++ db/derby/code/trunk/tools/jar/extraDBMSclasses.properties Fri Jun  7 19:44:14 2013
@@ -35,6 +35,7 @@ derby.module.vti.locktable=org.apache.de
 derby.module.vti.metadata.template=org.apache.derby.vti.VTIMetaDataTemplate
 derby.module.vti.ForeignTableVTI=org.apache.derby.vti.ForeignTableVTI
 derby.module.vti.StringColumnVTI=org.apache.derby.vti.StringColumnVTI
+derby.module.vti.XmlVTI=org.apache.derby.vti.XmlVTI
 derby.module.vti.updatabletemplate=org.apache.derby.vti.UpdatableVTITemplate
 derby.module.vti.transactiontable=org.apache.derby.diag.TransactionTable
 derby.module.vti.triggerold=org.apache.derby.catalog.TriggerOldTransitionRows



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