Java tutorial
/* $Id$ Copyright (C) 2003-2010 Virginia Tech. All rights reserved. SEE LICENSE FOR MORE INFORMATION Author: Middleware Services Email: middleware@vt.edu Version: $Revision$ Updated: $Date$ */ package edu.vt.middleware.ldap.servlets; import java.io.BufferedWriter; import java.io.IOException; import java.io.OutputStreamWriter; import javax.servlet.ServletConfig; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import edu.vt.middleware.ldap.Ldap; import edu.vt.middleware.ldap.LdapConfig; import edu.vt.middleware.ldap.dsml.DsmlSearch; import edu.vt.middleware.ldap.ldif.LdifSearch; import edu.vt.middleware.ldap.pool.BlockingLdapPool; import edu.vt.middleware.ldap.pool.DefaultLdapFactory; import edu.vt.middleware.ldap.pool.LdapPool; import edu.vt.middleware.ldap.pool.LdapPoolConfig; import edu.vt.middleware.ldap.pool.SharedLdapPool; import edu.vt.middleware.ldap.pool.SoftLimitLdapPool; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * <code>SearchServlet</code> is a servlet which queries an LDAP and returns the * result as LDIF or DSML. The following init params can be set for this * servlet: edu.vt.middleware.ldap.servlets.propertiesFile - to load ldap * properties from edu.vt.middleware.ldap.servlets.outputFormat - type of output * to produce, 'ldif' or 'dsml' Example: * http://www.server.com/Search?query=uid=dfisher If you need to pass complex * queries, such as (&(cn=daniel*)(surname=fisher)), then the query must be form * encoded. If you only want to receive a subset of attributes those can be * specified. Example: * http://www.server.com/Search?query=uid=dfisher&attrs=givenname&attrs=surname * * <h3>LDIF</h3> * * <p>The content returned by the servlet is of type text/plain.</p> * <hr/> * <h3>DSML</h3> * * <p>The content returned by the servlet is of type text/xml, if you want to * receive the content as text/plain that can be specified as well. Example: * http://www.server.com/Search?query=uid=dfisher&content-type=text By default * DSML version 1 is returned, if you want to receive DSML version 2 then you * must pass in the dsml-version parameter. Example: * http://www.server.com/Search?query=uid=dfisher&dsml-version=2</p> * * @author Middleware Services * @version $Revision$ $Date$ */ public final class SearchServlet extends HttpServlet { /** serial version uid. */ private static final long serialVersionUID = 1731614499970954068L; /** Types of available pools. */ private enum PoolType { /** blocking. */ BLOCKING, /** soft limit. */ SOFTLIMIT, /** shared. */ SHARED } /** Types of available output. */ private enum OutputType { /** LDIF output type. */ LDIF, /** DSML output type. */ DSML } /** Log for this class. */ private final Log logger = LogFactory.getLog(SearchServlet.class); /** Type of output to produce. */ private OutputType output; /** Object to use for searching. */ private LdifSearch ldifSearch; /** Object to use for searching. */ private DsmlSearch dsmlv1Search; /** Object to use for searching. */ private DsmlSearch dsmlv2Search; /** * Initialize this servlet. * * @param config <code>ServletConfig</code> * * @throws ServletException if an error occurs */ public void init(final ServletConfig config) throws ServletException { super.init(config); final String propertiesFile = getInitParameter(ServletConstants.PROPERTIES_FILE); if (this.logger.isDebugEnabled()) { this.logger.debug(ServletConstants.PROPERTIES_FILE + " = " + propertiesFile); } final LdapConfig ldapConfig = LdapConfig .createFromProperties(SearchServlet.class.getResourceAsStream(propertiesFile)); final String poolPropertiesFile = getInitParameter(ServletConstants.POOL_PROPERTIES_FILE); if (this.logger.isDebugEnabled()) { this.logger.debug(ServletConstants.POOL_PROPERTIES_FILE + " = " + poolPropertiesFile); } final LdapPoolConfig ldapPoolConfig = LdapPoolConfig .createFromProperties(SearchServlet.class.getResourceAsStream(poolPropertiesFile)); LdapPool<Ldap> ldapPool = null; final String poolType = getInitParameter(ServletConstants.POOL_TYPE); if (this.logger.isDebugEnabled()) { this.logger.debug(ServletConstants.POOL_TYPE + " = " + poolType); } if (PoolType.BLOCKING == PoolType.valueOf(poolType)) { ldapPool = new BlockingLdapPool(ldapPoolConfig, new DefaultLdapFactory(ldapConfig)); } else if (PoolType.SOFTLIMIT == PoolType.valueOf(poolType)) { ldapPool = new SoftLimitLdapPool(ldapPoolConfig, new DefaultLdapFactory(ldapConfig)); } else if (PoolType.SHARED == PoolType.valueOf(poolType)) { ldapPool = new SharedLdapPool(ldapPoolConfig, new DefaultLdapFactory(ldapConfig)); } else { throw new ServletException("Unknown pool type: " + poolType); } ldapPool.initialize(); this.ldifSearch = new LdifSearch(ldapPool); this.dsmlv1Search = new DsmlSearch(ldapPool); this.dsmlv1Search.setVersion(DsmlSearch.Version.ONE); this.dsmlv2Search = new DsmlSearch(ldapPool); this.dsmlv2Search.setVersion(DsmlSearch.Version.TWO); String outputType = getInitParameter(ServletConstants.OUTPUT_FORMAT); if (outputType == null) { outputType = ServletConstants.DEFAULT_OUTPUT_FORMAT; } if (this.logger.isDebugEnabled()) { this.logger.debug(ServletConstants.OUTPUT_FORMAT + " = " + outputType); } this.output = OutputType.valueOf(outputType); } /** * Handle all requests sent to this servlet. * * @param request <code>HttpServletRequest</code> * @param response <code>HttpServletResponse</code> * * @throws ServletException if an error occurs * @throws IOException if an error occurs */ public void service(final HttpServletRequest request, final HttpServletResponse response) throws ServletException, IOException { if (this.logger.isInfoEnabled()) { this.logger.info("Performing search: " + request.getParameter("query") + " for attributes: " + request.getParameter("attrs")); } try { if (this.output == OutputType.LDIF) { response.setContentType("text/plain"); this.ldifSearch.search(request.getParameter("query"), request.getParameterValues("attrs"), new BufferedWriter(new OutputStreamWriter(response.getOutputStream()))); } else { final String content = request.getParameter("content-type"); if (content != null && content.equalsIgnoreCase("text")) { response.setContentType("text/plain"); } else { response.setContentType("text/xml"); } final String dsmlVersion = request.getParameter("dsml-version"); if ("2".equals(dsmlVersion)) { this.dsmlv2Search.search(request.getParameter("query"), request.getParameterValues("attrs"), new BufferedWriter(new OutputStreamWriter(response.getOutputStream()))); } else { this.dsmlv1Search.search(request.getParameter("query"), request.getParameterValues("attrs"), new BufferedWriter(new OutputStreamWriter(response.getOutputStream()))); } } } catch (Exception e) { if (this.logger.isErrorEnabled()) { this.logger.error("Error performing search", e); } throw new ServletException(e); } } /** * Called by the servlet container to indicate to a servlet that the servlet * is being taken out of service. */ public void destroy() { try { // all search instances share the same pool // only need to close one of them this.ldifSearch.close(); } finally { super.destroy(); } } }