Metacat

/**

 *  '$RCSfile$'

 *    Purpose: A Class that loads eml-access.xml file containing ACL 

 *             for a metadata document into relational DB

 *  Copyright: 2000 Regents of the University of California and the

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Jivka Bojilova

 *    Release: @release@

 *

 *   '$Author: bojilova $'

 *     '$Date: 2000-11-21 10:04:37 -0800 (Tue, 21 Nov 2000) $'

 * '$Revision: 555 $'

 */

package edu.ucsb.nceas.metacat;

import java.io.*;

import java.sql.*;

import java.util.Stack;

import java.util.Vector;

import org.xml.sax.Attributes;

import org.xml.sax.InputSource;

import org.xml.sax.SAXException;

import org.xml.sax.SAXParseException;

import org.xml.sax.XMLReader;

import org.xml.sax.helpers.XMLReaderFactory;

import org.xml.sax.helpers.DefaultHandler;

/** 

 * A Class that loads eml-access.xml file containing ACL for a metadata

 * document into relational DB. It extends DefaultHandler class to handle

 * SAX parsing events when processing the XML stream.

 */

public class AccessControlList extends DefaultHandler {

  static final int ALL = 1;

  static final int WRITE = 2;

  static final int READ = 4;

  private Connection  conn;

  private String docid;

  private String parserName;

  private Stack elementStack;

  private Vector allow  = new Vector();

  private Vector begin1 = new Vector();

  private Vector end1   = new Vector();

  private Vector count1 = new Vector();

  private Vector denyv  = new Vector();

  private Vector begin2 = new Vector();

  private Vector end2   = new Vector();

  private Vector count2 = new Vector();

  private String principal_name = "";

  private String principal_type;

  private int permission = 0;

  private String begin_time;

  private String end_time;

  private int count;

  private int deny;

  /**

   * Construct an instance of the AccessControlList class.

   * It parse acl file and loads acl data into db connection.

   *

   * @param conn the JDBC connection where acl data are loaded

   * @param docid the Accession# of the document with the acl data

   * @param acl the acl file containing acl data for the document

   */

  public AccessControlList ( Connection conn, String docid, Reader acl )

                  throws SAXException, IOException, ClassNotFoundException 

  {

    // Get an instance of the parser

    MetaCatUtil util = new MetaCatUtil();

    String parserName = util.getOption("saxparser");

    this.conn = conn;

    this.docid = docid;

    this.parserName = parserName;

    elementStack = new Stack();

    // Initialize the parser and read the queryspec

    XMLReader parser = initializeParser();

    parser.parse(new InputSource(acl));

  }

  public AccessControlList( Connection conn, String docid, String aclfilename )

                  throws SAXException, IOException, ClassNotFoundException 

  {

    this(conn,docid,new FileReader(new File(aclfilename).toString()));

  }

  /**

   * Set up the SAX parser for reading the XML serialized ACL

   */

  private XMLReader initializeParser() throws SAXException 

  {

    XMLReader parser = null;

    // Get an instance of the parser

    parser = XMLReaderFactory.createXMLReader(parserName);

    // Set the ContentHandler to this instance

    parser.setContentHandler(this);

    // Set the ErrorHandler to this instance

    parser.setErrorHandler(this);

    return parser;

  }

  /**

   * callback method used by the SAX Parser when the start tag of an 

   * element is detected. Used in this context to parse and store

   * the acl information in class variables.

   */

  public void startElement (String uri, String localName, 

                            String qName, Attributes atts) 

         throws SAXException 

  {

    BasicNode currentNode = new BasicNode(localName);

    if (atts != null) {

      int len = atts.getLength();

      for (int i = 0; i < len; i++) {

        currentNode.setAttribute(atts.getLocalName(i), atts.getValue(i));

      }

    }

    elementStack.push(currentNode); 

  }

  /**

   * callback method used by the SAX Parser when the text sequences of an 

   * xml stream are detected. Used in this context to parse and store

   * the acl information in class variables.

   */

  public void characters(char ch[], int start, int length)

         throws SAXException 

  {

    String inputString = new String(ch, start, length);

    BasicNode currentNode = (BasicNode)elementStack.peek(); 

    String currentTag = currentNode.getTagName();

    if (currentTag.equals("groupName")) {

      principal_name = inputString;

      principal_type = "group";

    } else if (currentTag.equals("userName")) {

      principal_name = inputString;

      principal_type = "user";

    } else if (currentTag.equals("permission")) {

      if ( inputString.trim().toUpperCase().equals("READ") ) {

        permission = permission | READ;

      } else if ( inputString.trim().toUpperCase().equals("WRITE") ) {

        permission = permission | WRITE;

      } else if ( inputString.trim().toUpperCase().equals("ALL") ) {

        permission = permission | ALL;

      }

    } else if (currentTag.equals("duration") && 

               begin_time == null && end_time == null ) {

      try {

        begin_time = inputString.substring(0, inputString.indexOf(" "));

        end_time = inputString.substring(inputString.indexOf(" ")+1);

      } catch (StringIndexOutOfBoundsException se) {

        begin_time = inputString;

      }

    } else if (currentTag.equals("count") && count == 0 ) {

      count = (new Integer(inputString.trim())).intValue();

    }

  }

  /**

   * callback method used by the SAX Parser when the end tag of an 

   * element is detected. Used in this context to parse and store

   * the acl information in class variables.

   */

  public void endElement (String uri, String localName, String qName)

         throws SAXException 

  {

    BasicNode leaving = (BasicNode)elementStack.pop(); 

    if ( leaving.getTagName().equals("allow") && permission > 0 ) {

      // collect allowed permissions in a Vector variable allow

      allow.add(new Integer(permission));

      begin1.add(begin_time);

      end1.add(end_time);

      count1.add(new Integer(count));

      // reset the allowed permission

      permission = 0;

      begin_time = null;

      end_time = null;

      count = 0;

    } else if ( leaving.getTagName().equals("deny") && permission > 0 ) {

      // collect denied permissions in a Vector variable denyv

      denyv.add(new Integer(permission));

      begin2.add(begin_time);

      end2.add(end_time);

      count2.add(new Integer(count));

      // reset the denied permission

      permission = 0;

      begin_time = null;

      end_time = null;

      count = 0;

    } else if ( leaving.getTagName().equals("accessControl") ) {

      // when order attribute for <accessControl> is specified to "denyFirst"

      // exclude the allowed permissions from the list of denied ones

      if ( leaving.getAttribute("order").equals("denyFirst") ) {

        for ( int i = 0; i < allow.size(); i++ ) {

          for ( int j = 0; j < denyv.size(); j++ ) {

            denyv.setElementAt( 

            new Integer(((Integer)denyv.elementAt(j)).intValue() & 

                        ~((Integer)allow.elementAt(i)).intValue()), j);

          }

        }

      }

      // insert into db connection collected permissions for the principal

      try {

        insertPermissions();

      } catch (SQLException sqle) {

        throw new SAXException(sqle);

      }

      // reset the list of allowed and denied permissions 

      // for use for the next principal

      allow  = new Vector();

      begin1 = new Vector();

      end1   = new Vector();

      count1 = new Vector();

      denyv  = new Vector();

      begin2 = new Vector();

      end2   = new Vector();

      count2 = new Vector();

    } else if ( leaving.getTagName().equals("user") || 

                leaving.getTagName().equals("group") ) {

//      try {                  

//        principal_name = 

//        principal_name.substring(0, principal_name.lastIndexOf("."));

//      } catch (StringIndexOutOfBoundsException se) {

        // reset the name of the current principal for next use

        principal_name = "";

//      }

    }

  }

  /** Insert into db connection collected permissions for a principal */

  private void insertPermissions() 

          throws SQLException 

  {

    PreparedStatement pstmt;

    // 

    try {

      pstmt = conn.prepareStatement(

              "INSERT INTO xml_access " + 

              "(docid, principal_name, principal_type, " +

              "permission, begin_time, end_time, ticket_counter, deny)" +

              "VALUES (?, ?, ?, ?, to_date(?,'mm/dd/yy'), " +

              " to_date(?,'mm/dd/yy'), ?, ?)");

      // Bind the values to the query

      pstmt.setString(1, docid);

      pstmt.setString(2, principal_name);

      pstmt.setString(3, principal_type);

      // insert the allowed permissions first

      for ( int i = 0; i < allow.size(); i++ ) {

        pstmt.setInt(4, ((Integer)allow.elementAt(i)).intValue());

        pstmt.setString(5, (String)begin1.elementAt(i));

        pstmt.setString(6, (String)end1.elementAt(i));

        if ( ((Integer)count1.elementAt(i)).intValue() > 0 ) {

          pstmt.setString(7, "" + ((Integer)count1.elementAt(i)).intValue());

        } else {

          pstmt.setString(7, "");

        }

        pstmt.setString(8, "");

        pstmt.execute();

      }

      // insert the denied permissions

      for ( int i = 0; i < denyv.size(); i++ ) {

        if ( ((Integer)denyv.elementAt(i)).intValue() <= 0 ) {

          continue;

        }

        pstmt.setInt(4, ((Integer)denyv.elementAt(i)).intValue());

        pstmt.setString(5, (String)begin2.elementAt(i));

        pstmt.setString(6, (String)end2.elementAt(i));

        if ( ((Integer)count2.elementAt(i)).intValue() > 0 ) {

          pstmt.setString(7, "" + ((Integer)count2.elementAt(i)).intValue());

        } else {

          pstmt.setString(7, "");

        }

        pstmt.setString(8, "" + 1);

        pstmt.execute();

      }

    } catch (SQLException e) {

      throw new 

      SQLException("AccessControlList.insertPermissions(): " + e.getMessage());

    }

  }

}