Java tutorial
/********************************************************************************** * $URL: https://source.sakaiproject.org/contrib/etudes/sakai-jforum/tags/2.9.11/jforum-tool/src/java/org/etudes/jforum/dao/oracle/OracleUtils.java $ * $Id: OracleUtils.java 83559 2013-04-30 19:03:29Z murthy@etudes.org $ *********************************************************************************** * * Copyright (c) 2008, 2009, 2010 Etudes, Inc. * * Licensed 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. * * Portions completed before July 1, 2004 Copyright (c) 2003, 2004 Rafael Steil, All rights reserved, licensed under the BSD license. * http://www.opensource.org/licenses/bsd-license.php * * Redistribution and use in source and binary forms, * with or without modification, are permitted provided * that the following conditions are met: * * 1) Redistributions of source code must retain the above * copyright notice, this list of conditions and the * following disclaimer. * 2) Redistributions in binary form must reproduce the * above copyright notice, this list of conditions and * the following disclaimer in the documentation and/or * other materials provided with the distribution. * 3) Neither the name of "Rafael Steil" nor * the names of its contributors may be used to endorse * or promote products derived from this software without * specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT * HOLDERS AND CONTRIBUTORS "AS IS" AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER * IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE ***********************************************************************************/ package org.etudes.jforum.dao.oracle; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.Reader; import java.io.Writer; import java.sql.Blob; import java.sql.Clob; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.etudes.jforum.JForum; /** * @author Dmitriy Kiriy */ public class OracleUtils { private static final Log logger = LogFactory.getLog(OracleUtils.class); public static String readBlobUTF16BinaryStream(ResultSet rs, String fieldName) throws IOException, SQLException { Blob clob = rs.getBlob(fieldName); InputStream is = clob.getBinaryStream(); StringBuffer sb = new StringBuffer(); int readedBytes = 0; int bufferSize = 4096; do { byte[] bytes = new byte[bufferSize]; readedBytes = is.read(bytes); if (readedBytes > 0) { String readed = new String(bytes, 0, readedBytes, "UTF-16"); sb.append(readed); } } while (readedBytes == bufferSize); is.close(); return sb.toString(); } /** * The query should look like: * * SELECT blob_field from any_table WHERE id = ? FOR UPDATE * * BUT KEEP IN MIND: * * When you insert record in previous step, it should go with empty_blob() like: * * INSERT INTO jforum_posts_text ( post_text ) VALUES (EMPTY_BLOB()) * * @param query * @param idForQuery * @param value * @throws IOException * @throws SQLException */ public static void writeBlobUTF16BinaryStream(String query, int idForQuery, String value) throws IOException, SQLException { PreparedStatement p = JForum.getConnection().prepareStatement(query); p.setInt(1, idForQuery); ResultSet rs = p.executeQuery(); rs.next(); Blob postText = rs.getBlob(1); //wipe out the Blob contents postText.truncate(0); if (logger.isDebugEnabled()) logger.debug("post test is a " + postText.getClass().getName()); // OutputStream blobWriter = ((oracle.sql.BLOB)postText).setBinaryStream(0L); OutputStream blobWriter = postText.setBinaryStream(0L); blobWriter.write(value.getBytes("UTF-16")); blobWriter.flush(); blobWriter.close(); rs.close(); p.close(); } /** * Writes clob to database * @param query * @param idForQuery * @param value * @throws IOException * @throws SQLException */ public static void writeClobUTF16BinaryStream(String query, int idForQuery, String value) throws IOException, SQLException { PreparedStatement p = JForum.getConnection().prepareStatement(query); p.setInt(1, idForQuery); ResultSet rs = p.executeQuery(); rs.next(); Clob clobval = rs.getClob(1); if (logger.isDebugEnabled()) logger.debug("clobval is " + clobval.getClass().getName()); Writer clobWriter = clobval.setCharacterStream(0L); char[] cbuffer = new char[value.length()]; int srcBegin = 0, dstBegin = 0; value.getChars(srcBegin, value.length(), cbuffer, dstBegin); clobWriter.write(cbuffer); clobWriter.close(); rs.close(); p.close(); } /** * read clob into a string * @param rs * @param fieldName * @return * @throws IOException * @throws SQLException */ public static String readClobUTF16BinaryStream(ResultSet rs, String fieldName) throws IOException, SQLException { Clob clob = rs.getClob(fieldName); Reader clobStream = clob.getCharacterStream(); StringBuffer clobData = new StringBuffer(); // Read from the Clob stream and write to the stringbuffer int nchars = 0; char[] buffer = new char[4096]; while ((nchars = clobStream.read(buffer)) != -1) clobData.append(buffer, 0, nchars); clobStream.close(); return clobData.toString(); } }