Java tutorial
/* * RHQ Management Platform * Copyright (C) 2005-2008 Red Hat, Inc. * All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation version 2 of the License. * * This program 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 for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ package org.rhq.plugins.mysql; import java.sql.Connection; import java.sql.ResultSet; import java.sql.ResultSetMetaData; import java.sql.SQLException; import java.sql.Statement; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.rhq.core.domain.configuration.Configuration; import org.rhq.core.pluginapi.availability.AvailabilityFacet; import org.rhq.core.pluginapi.inventory.InvalidPluginConfigurationException; import org.rhq.core.pluginapi.inventory.ResourceContext; import org.rhq.core.pluginapi.operation.OperationFacet; import org.rhq.core.pluginapi.operation.OperationResult; import org.rhq.plugins.database.DatabaseComponent; import org.rhq.plugins.database.DatabaseQueryUtility; import org.rhq.core.domain.configuration.PropertySimple; import org.rhq.core.domain.measurement.AvailabilityType; /** * * @author Steve Millidge (C2B2 Consulting Limited) */ public class MySqlDatabaseComponent implements DatabaseComponent, AvailabilityFacet, OperationFacet { private ResourceContext resourceContext; private MySqlComponent parent; private String databaseName; private static Log log = LogFactory.getLog(MySqlDatabaseComponent.class); @Override public Connection getConnection() { return parent.getConnection(); } @Override public void removeConnection() { parent.removeConnection(); } @Override public void start(ResourceContext rc) throws InvalidPluginConfigurationException, Exception { resourceContext = rc; databaseName = rc.getResourceKey(); parent = (MySqlComponent) resourceContext.getParentResourceComponent(); } public String getName() { return databaseName; } @Override public void stop() { } @Override public AvailabilityType getAvailability() { AvailabilityType result = AvailabilityType.DOWN; if (log.isDebugEnabled()) { log.debug("Availability check for " + databaseName); } Connection conn = getConnection(); if (conn != null) { Statement statement = null; ResultSet resultSet = null; try { statement = conn.createStatement(); resultSet = statement.executeQuery("SHOW DATABASES LIKE '" + databaseName + "'"); if (resultSet.next()) { if (resultSet.getString(1).equalsIgnoreCase(databaseName)) { result = AvailabilityType.UP; } } } catch (SQLException e) { if (log.isDebugEnabled()) { log.debug("Got Exception when determining database availability", e); } } finally { DatabaseQueryUtility.close(statement, resultSet); } } return result; } @Override public OperationResult invokeOperation(String name, Configuration parameters) throws InterruptedException, Exception { if ("invokeSql".equals(name)) { Statement stmt = null; ResultSet rs = null; try { stmt = getConnection().createStatement(); String sql = parameters.getSimple("sql").getStringValue(); OperationResult result = new OperationResult(); if (parameters.getSimple("type").getStringValue().equals("update")) { int updateCount = stmt.executeUpdate(sql); result.getComplexResults() .put(new PropertySimple("result", "Query updated " + updateCount + " rows")); } else { rs = stmt.executeQuery(parameters.getSimple("sql").getStringValue()); ResultSetMetaData md = rs.getMetaData(); StringBuilder buf = new StringBuilder(); int rowCount = 0; buf.append("<table>"); buf.append("<th>"); for (int i = 1; i <= md.getColumnCount(); i++) { buf.append("<td>"); buf.append(md.getColumnName(i) + " (" + md.getColumnTypeName(i) + ")"); buf.append("</td>"); } buf.append("</th>"); while (rs.next()) { rowCount++; buf.append("<tr>"); for (int i = 1; i <= md.getColumnCount(); i++) { buf.append("<td>"); buf.append(rs.getString(i)); buf.append("</td>"); } buf.append("</tr>"); } buf.append("</table>"); result.getComplexResults() .put(new PropertySimple("result", "Query returned " + rowCount + " rows")); result.getComplexResults().put(new PropertySimple("contents", buf.toString())); } return result; } finally { if (rs != null) { rs.close(); } if (stmt != null) { stmt.close(); } } } else { throw new UnsupportedOperationException("Operation [" + name + "] is not supported yet."); } } }