| /* |
| * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package com.sun.rowset.internal; |
| |
| import java.sql.*; |
| import javax.sql.*; |
| import javax.naming.*; |
| import java.io.*; |
| import java.lang.reflect.*; |
| |
| import com.sun.rowset.*; |
| import javax.sql.rowset.*; |
| import javax.sql.rowset.spi.*; |
| |
| /** |
| * The facility called by the <code>RIOptimisticProvider</code> object |
| * internally to read data into it. The calling <code>RowSet</code> object |
| * must have implemented the <code>RowSetInternal</code> interface |
| * and have the standard <code>CachedRowSetReader</code> object set as its |
| * reader. |
| * <P> |
| * This implementation always reads all rows of the data source, |
| * and it assumes that the <code>command</code> property for the caller |
| * is set with a query that is appropriate for execution by a |
| * <code>PreparedStatement</code> object. |
| * <P> |
| * Typically the <code>SyncFactory</code> manages the <code>RowSetReader</code> and |
| * the <code>RowSetWriter</code> implementations using <code>SyncProvider</code> objects. |
| * Standard JDBC RowSet implementations provide an object instance of this |
| * reader by invoking the <code>SyncProvider.getRowSetReader()</code> method. |
| * |
| * @author Jonathan Bruce |
| * @see javax.sql.rowset.spi.SyncProvider |
| * @see javax.sql.rowset.spi.SyncFactory |
| * @see javax.sql.rowset.spi.SyncFactoryException |
| */ |
| public class CachedRowSetReader implements RowSetReader, Serializable { |
| |
| /** |
| * The field that keeps track of whether the writer associated with |
| * this <code>CachedRowSetReader</code> object's rowset has been called since |
| * the rowset was populated. |
| * <P> |
| * When this <code>CachedRowSetReader</code> object reads data into |
| * its rowset, it sets the field <code>writerCalls</code> to 0. |
| * When the writer associated with the rowset is called to write |
| * data back to the underlying data source, its <code>writeData</code> |
| * method calls the method <code>CachedRowSetReader.reset</code>, |
| * which increments <code>writerCalls</code> and returns <code>true</code> |
| * if <code>writerCalls</code> is 1. Thus, <code>writerCalls</code> equals |
| * 1 after the first call to <code>writeData</code> that occurs |
| * after the rowset has had data read into it. |
| * |
| * @serial |
| */ |
| private int writerCalls = 0; |
| |
| private boolean userCon = false; |
| |
| private int startPosition; |
| |
| private JdbcRowSetResourceBundle resBundle; |
| |
| public CachedRowSetReader() { |
| try { |
| resBundle = JdbcRowSetResourceBundle.getJdbcRowSetResourceBundle(); |
| } catch(IOException ioe) { |
| throw new RuntimeException(ioe); |
| } |
| } |
| |
| |
| /** |
| * Reads data from a data source and populates the given |
| * <code>RowSet</code> object with that data. |
| * This method is called by the rowset internally when |
| * the application invokes the method <code>execute</code> |
| * to read a new set of rows. |
| * <P> |
| * After clearing the rowset of its contents, if any, and setting |
| * the number of writer calls to <code>0</code>, this reader calls |
| * its <code>connect</code> method to make |
| * a connection to the rowset's data source. Depending on which |
| * of the rowset's properties have been set, the <code>connect</code> |
| * method will use a <code>DataSource</code> object or the |
| * <code>DriverManager</code> facility to make a connection to the |
| * data source. |
| * <P> |
| * Once the connection to the data source is made, this reader |
| * executes the query in the calling <code>CachedRowSet</code> object's |
| * <code>command</code> property. Then it calls the rowset's |
| * <code>populate</code> method, which reads data from the |
| * <code>ResultSet</code> object produced by executing the rowset's |
| * command. The rowset is then populated with this data. |
| * <P> |
| * This method's final act is to close the connection it made, thus |
| * leaving the rowset disconnected from its data source. |
| * |
| * @param caller a <code>RowSet</code> object that has implemented |
| * the <code>RowSetInternal</code> interface and had |
| * this <code>CachedRowSetReader</code> object set as |
| * its reader |
| * @throws SQLException if there is a database access error, there is a |
| * problem making the connection, or the command property has not |
| * been set |
| */ |
| public void readData(RowSetInternal caller) throws SQLException |
| { |
| Connection con = null; |
| try { |
| CachedRowSet crs = (CachedRowSet)caller; |
| |
| // Get rid of the current contents of the rowset. |
| |
| /** |
| * Checking added to verify whether page size has been set or not. |
| * If set then do not close the object as certain parameters need |
| * to be maintained. |
| */ |
| |
| if(crs.getPageSize() == 0 && crs.size() >0 ) { |
| // When page size is not set, |
| // crs.size() will show the total no of rows. |
| crs.close(); |
| } |
| |
| writerCalls = 0; |
| |
| // Get a connection. This reader assumes that the necessary |
| // properties have been set on the caller to let it supply a |
| // connection. |
| userCon = false; |
| |
| con = this.connect(caller); |
| |
| // Check our assumptions. |
| if (con == null || crs.getCommand() == null) |
| throw new SQLException(resBundle.handleGetObject("crsreader.connecterr").toString()); |
| |
| try { |
| con.setTransactionIsolation(crs.getTransactionIsolation()); |
| } catch (Exception ex) { |
| ; |
| } |
| // Use JDBC to read the data. |
| PreparedStatement pstmt = con.prepareStatement(crs.getCommand()); |
| // Pass any input parameters to JDBC. |
| |
| decodeParams(caller.getParams(), pstmt); |
| try { |
| pstmt.setMaxRows(crs.getMaxRows()); |
| pstmt.setMaxFieldSize(crs.getMaxFieldSize()); |
| pstmt.setEscapeProcessing(crs.getEscapeProcessing()); |
| pstmt.setQueryTimeout(crs.getQueryTimeout()); |
| } catch (Exception ex) { |
| /* |
| * drivers may not support the above - esp. older |
| * drivers being used by the bridge.. |
| */ |
| throw new SQLException(ex.getMessage()); |
| } |
| |
| if(crs.getCommand().toLowerCase().indexOf("select") != -1) { |
| // can be (crs.getCommand()).indexOf("select")) == 0 |
| // because we will be getting resultset when |
| // it may be the case that some false select query with |
| // select coming in between instead of first. |
| |
| // if ((crs.getCommand()).indexOf("?")) does not return -1 |
| // implies a Prepared Statement like query exists. |
| |
| ResultSet rs = pstmt.executeQuery(); |
| if(crs.getPageSize() == 0){ |
| crs.populate(rs); |
| } |
| else { |
| /** |
| * If page size has been set then create a ResultSet object that is scrollable using a |
| * PreparedStatement handle.Also call the populate(ResultSet,int) function to populate |
| * a page of data as specified by the page size. |
| */ |
| pstmt = con.prepareStatement(crs.getCommand(),ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE); |
| decodeParams(caller.getParams(), pstmt); |
| try { |
| pstmt.setMaxRows(crs.getMaxRows()); |
| pstmt.setMaxFieldSize(crs.getMaxFieldSize()); |
| pstmt.setEscapeProcessing(crs.getEscapeProcessing()); |
| pstmt.setQueryTimeout(crs.getQueryTimeout()); |
| } catch (Exception ex) { |
| /* |
| * drivers may not support the above - esp. older |
| * drivers being used by the bridge.. |
| */ |
| throw new SQLException(ex.getMessage()); |
| } |
| rs = pstmt.executeQuery(); |
| crs.populate(rs,startPosition); |
| } |
| rs.close(); |
| } else { |
| pstmt.executeUpdate(); |
| } |
| |
| // Get the data. |
| pstmt.close(); |
| try { |
| con.commit(); |
| } catch (SQLException ex) { |
| ; |
| } |
| // only close connections we created... |
| if (getCloseConnection() == true) |
| con.close(); |
| } |
| catch (SQLException ex) { |
| // Throw an exception if reading fails for any reason. |
| throw ex; |
| } finally { |
| try { |
| // only close connections we created... |
| if (con != null && getCloseConnection() == true) { |
| try { |
| if (!con.getAutoCommit()) { |
| con.rollback(); |
| } |
| } catch (Exception dummy) { |
| /* |
| * not an error condition, we're closing anyway, but |
| * we'd like to clean up any locks if we can since |
| * it is not clear the connection pool will clean |
| * these connections in a timely manner |
| */ |
| } |
| con.close(); |
| con = null; |
| } |
| } catch (SQLException e) { |
| // will get exception if something already went wrong, but don't |
| // override that exception with this one |
| } |
| } |
| } |
| |
| /** |
| * Checks to see if the writer associated with this reader needs |
| * to reset its state. The writer will need to initialize its state |
| * if new contents have been read since the writer was last called. |
| * This method is called by the writer that was registered with |
| * this reader when components were being wired together. |
| * |
| * @return <code>true</code> if writer associated with this reader needs |
| * to reset the values of its fields; <code>false</code> otherwise |
| * @throws SQLException if an access error occurs |
| */ |
| public boolean reset() throws SQLException { |
| writerCalls++; |
| return writerCalls == 1; |
| } |
| |
| /** |
| * Establishes a connection with the data source for the given |
| * <code>RowSet</code> object. If the rowset's <code>dataSourceName</code> |
| * property has been set, this method uses the JNDI API to retrieve the |
| * <code>DataSource</code> object that it can use to make the connection. |
| * If the url, username, and password properties have been set, this |
| * method uses the <code>DriverManager.getConnection</code> method to |
| * make the connection. |
| * <P> |
| * This method is used internally by the reader and writer associated with |
| * the calling <code>RowSet</code> object; an application never calls it |
| * directly. |
| * |
| * @param caller a <code>RowSet</code> object that has implemented |
| * the <code>RowSetInternal</code> interface and had |
| * this <code>CachedRowSetReader</code> object set as |
| * its reader |
| * @return a <code>Connection</code> object that represents a connection |
| * to the caller's data source |
| * @throws SQLException if an access error occurs |
| */ |
| public Connection connect(RowSetInternal caller) throws SQLException { |
| |
| // Get a JDBC connection. |
| if (caller.getConnection() != null) { |
| // A connection was passed to execute(), so use it. |
| // As we are using a connection the user gave us we |
| // won't close it. |
| userCon = true; |
| return caller.getConnection(); |
| } |
| else if (((RowSet)caller).getDataSourceName() != null) { |
| // Connect using JNDI. |
| try { |
| Context ctx = new InitialContext(); |
| DataSource ds = (DataSource)ctx.lookup |
| (((RowSet)caller).getDataSourceName()); |
| |
| // Check for username, password, |
| // if it exists try getting a Connection handle through them |
| // else try without these |
| // else throw SQLException |
| |
| if(((RowSet)caller).getUsername() != null) { |
| return ds.getConnection(((RowSet)caller).getUsername(), |
| ((RowSet)caller).getPassword()); |
| } else { |
| return ds.getConnection(); |
| } |
| } |
| catch (javax.naming.NamingException ex) { |
| SQLException sqlEx = new SQLException(resBundle.handleGetObject("crsreader.connect").toString()); |
| sqlEx.initCause(ex); |
| throw sqlEx; |
| } |
| } else if (((RowSet)caller).getUrl() != null) { |
| // Connect using the driver manager. |
| return DriverManager.getConnection(((RowSet)caller).getUrl(), |
| ((RowSet)caller).getUsername(), |
| ((RowSet)caller).getPassword()); |
| } |
| else { |
| return null; |
| } |
| } |
| |
| /** |
| * Sets the parameter placeholders |
| * in the rowset's command (the given <code>PreparedStatement</code> |
| * object) with the parameters in the given array. |
| * This method, called internally by the method |
| * <code>CachedRowSetReader.readData</code>, reads each parameter, and |
| * based on its type, determines the correct |
| * <code>PreparedStatement.setXXX</code> method to use for setting |
| * that parameter. |
| * |
| * @param params an array of parameters to be used with the given |
| * <code>PreparedStatement</code> object |
| * @param pstmt the <code>PreparedStatement</code> object that is the |
| * command for the calling rowset and into which |
| * the given parameters are to be set |
| * @throws SQLException if an access error occurs |
| */ |
| private void decodeParams(Object[] params, |
| PreparedStatement pstmt) throws SQLException { |
| // There is a corresponding decodeParams in JdbcRowSetImpl |
| // which does the same as this method. This is a design flaw. |
| // Update the JdbcRowSetImpl.decodeParams when you update |
| // this method. |
| |
| // Adding the same comments to JdbcRowSetImpl.decodeParams. |
| |
| int arraySize; |
| Object[] param = null; |
| |
| for (int i=0; i < params.length; i++) { |
| if (params[i] instanceof Object[]) { |
| param = (Object[])params[i]; |
| |
| if (param.length == 2) { |
| if (param[0] == null) { |
| pstmt.setNull(i + 1, ((Integer)param[1]).intValue()); |
| continue; |
| } |
| |
| if (param[0] instanceof java.sql.Date || |
| param[0] instanceof java.sql.Time || |
| param[0] instanceof java.sql.Timestamp) { |
| System.err.println(resBundle.handleGetObject("crsreader.datedetected").toString()); |
| if (param[1] instanceof java.util.Calendar) { |
| System.err.println(resBundle.handleGetObject("crsreader.caldetected").toString()); |
| pstmt.setDate(i + 1, (java.sql.Date)param[0], |
| (java.util.Calendar)param[1]); |
| continue; |
| } |
| else { |
| throw new SQLException(resBundle.handleGetObject("crsreader.paramtype").toString()); |
| } |
| } |
| |
| if (param[0] instanceof Reader) { |
| pstmt.setCharacterStream(i + 1, (Reader)param[0], |
| ((Integer)param[1]).intValue()); |
| continue; |
| } |
| |
| /* |
| * What's left should be setObject(int, Object, scale) |
| */ |
| if (param[1] instanceof Integer) { |
| pstmt.setObject(i + 1, param[0], ((Integer)param[1]).intValue()); |
| continue; |
| } |
| |
| } else if (param.length == 3) { |
| |
| if (param[0] == null) { |
| pstmt.setNull(i + 1, ((Integer)param[1]).intValue(), |
| (String)param[2]); |
| continue; |
| } |
| |
| if (param[0] instanceof java.io.InputStream) { |
| switch (((Integer)param[2]).intValue()) { |
| case CachedRowSetImpl.UNICODE_STREAM_PARAM: |
| pstmt.setUnicodeStream(i + 1, |
| (java.io.InputStream)param[0], |
| ((Integer)param[1]).intValue()); |
| case CachedRowSetImpl.BINARY_STREAM_PARAM: |
| pstmt.setBinaryStream(i + 1, |
| (java.io.InputStream)param[0], |
| ((Integer)param[1]).intValue()); |
| case CachedRowSetImpl.ASCII_STREAM_PARAM: |
| pstmt.setAsciiStream(i + 1, |
| (java.io.InputStream)param[0], |
| ((Integer)param[1]).intValue()); |
| default: |
| throw new SQLException(resBundle.handleGetObject("crsreader.paramtype").toString()); |
| } |
| } |
| |
| /* |
| * no point at looking at the first element now; |
| * what's left must be the setObject() cases. |
| */ |
| if (param[1] instanceof Integer && param[2] instanceof Integer) { |
| pstmt.setObject(i + 1, param[0], ((Integer)param[1]).intValue(), |
| ((Integer)param[2]).intValue()); |
| continue; |
| } |
| |
| throw new SQLException(resBundle.handleGetObject("crsreader.paramtype").toString()); |
| |
| } else { |
| // common case - this catches all SQL92 types |
| pstmt.setObject(i + 1, params[i]); |
| continue; |
| } |
| } else { |
| // Try to get all the params to be set here |
| pstmt.setObject(i + 1, params[i]); |
| |
| } |
| } |
| } |
| |
| /** |
| * Assists in determining whether the current connection was created by this |
| * CachedRowSet to ensure incorrect connections are not prematurely terminated. |
| * |
| * @return a boolean giving the status of whether the connection has been closed. |
| */ |
| protected boolean getCloseConnection() { |
| if (userCon == true) |
| return false; |
| |
| return true; |
| } |
| |
| /** |
| * This sets the start position in the ResultSet from where to begin. This is |
| * called by the Reader in the CachedRowSetImpl to set the position on the page |
| * to begin populating from. |
| * @param pos integer indicating the position in the <code>ResultSet</code> to begin |
| * populating from. |
| */ |
| public void setStartPosition(int pos){ |
| startPosition = pos; |
| } |
| |
| private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException { |
| // Default state initialization happens here |
| ois.defaultReadObject(); |
| // Initialization of Res Bundle happens here . |
| try { |
| resBundle = JdbcRowSetResourceBundle.getJdbcRowSetResourceBundle(); |
| } catch(IOException ioe) { |
| throw new RuntimeException(ioe); |
| } |
| |
| } |
| |
| static final long serialVersionUID =5049738185801363801L; |
| } |
