servicelocator.java

用struts,spring实现网上商店的功能！！

package shopping.util;



import java.net.*;
import java.util.*;
import javax.ejb.*;
import javax.jms.*;
import java.rmi.RemoteException;
import javax.naming.*;
import javax.rmi.*;
import javax.sql.*;
import javax.transaction.*;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
 * <p>Title: KnowledgeManagement</p>
 *
 * <p>Description: </p>
 *
 * <p>Copyright: Copyright (c) 2009</p>
 *
 * <p>Company: GZ-Giant</p>
 *
 * @author Alan
 * @version 2.0
 */
public class ServiceLocator {

  private InitialContext ic;
  private Map cache = Collections.synchronizedMap(new HashMap());
  private static ServiceLocator instance = new ServiceLocator();
  public static ApplicationContext ctx = new ClassPathXmlApplicationContext("/applicationContext-ejb-config.xml");
  /**
   * 获取类实例
   * @return ServiceLocator
   */
  public static ServiceLocator getInstance() {
    return instance;
  }
  /**
   * 类初始化
   * @throws ServiceLocatorException
   */
  private ServiceLocator() throws ServiceLocatorException {
    try {
        ic = new InitialContext();
    }
    catch (Exception e) {
      throw new ServiceLocatorException(e);
    }
  }
  /**
   * 根据数据源名称获取数据源
   * @param dataSourceName String
   * @return DataSource
   * @throws ServiceLocatorException
   */
  public DataSource getDataSource(String dataSourceName) throws ServiceLocatorException {
    DataSource dataSource = (DataSource) cache.get(dataSourceName);
    if (dataSource == null) {
      try {
        dataSource = (DataSource) ic.lookup(dataSourceName);
        cache.put(dataSourceName, dataSource);
      }
      catch (Exception e) {
        throw new ServiceLocatorException(e);
      }
    }
    return dataSource;
  }
  /**
   * 获取数据源
   * @param dataSourceName String
   * @param callerObj Object
   * @return DataSource
   * @throws ServiceLocatorException
   */
  public DataSource getDataSource(String dataSourceName, Object callerObj) throws
      ServiceLocatorException {
    DataSource dataSource = (DataSource) cache.get(dataSourceName);
    if (dataSource == null) {
      try {
        System.out.println(dataSourceName+dataSourceName);
        dataSource = (DataSource) ic.lookup(dataSourceName);
        cache.put(dataSourceName, dataSource);
      }
      catch (Exception e) {
        throw new ServiceLocatorException(e);
      }
    }
    return dataSource;
  }
  /**
   *
   * @param envName String
   * @return URL
   * @throws ServiceLocatorException
   */
  public URL getUrl(String envName) throws ServiceLocatorException {
    try {
      return (URL) ic.lookup(envName);
    }
    catch (Exception e) {
      throw new ServiceLocatorException(e);
    }
  }

  /**
   * @return the boolean value corresponding
   * to the env entry such as SEND_CONFIRMATION_MAIL property.
   */
  public boolean getBoolean(String envName) throws ServiceLocatorException {
    try {
      return ( (Boolean) ic.lookup(envName)).booleanValue();
    }
    catch (Exception e) {
      throw new ServiceLocatorException(e);
    }
  }

  /**
   * @return the String value corresponding
   * to the env entry name.
   */
  public String getString(String envName) throws ServiceLocatorException {
    try {
      return (String) ic.lookup(envName);
    }
    catch (Exception e) {
      throw new ServiceLocatorException(e);
    }
  }
  /**
   * getCatchList
   *
   * @param jndiName String
   * @return Map
   */
  public Map getCatchList(String jndiName) {
    Map catchListMap = null;
    try {
      catchListMap = (Map) ic.lookup(jndiName);
    }
    catch (NamingException ex) {
      //Debug.print("\u00CE\u00B4\u00C4\u00DC\u00BB\u00F1\u00C8\u00A1\u00BB\u00BA\u00B4\u00E6\u00C1\u00D0±í" + jndiName + "\u00A3\u00BA" + ex.toString(), this);
    }
    return catchListMap;
  }

  /**
   * setCatchList
   *
   * @param jndiName String
   * @param catchListMap Map
   * @return boolean
   */
  public boolean setCatchList(String jndiName, Map catchListMap) {
    try {
      ic.rebind(jndiName, catchListMap);
    }catch (NamingException ex) {
      //Debug.print("绑定缓存列表时出错" + ex.toString(), this);
      return false;
    }
    return true;
  }
  public EJBHome getRemoteHome(String jndiHomeName, Class className) throws ServiceLocatorException {
    EJBHome home = (EJBHome) cache.get(jndiHomeName);
    if (home == null) {
      try {
        Object objref = ic.lookup(jndiHomeName);
        Object obj = PortableRemoteObject.narrow(objref, className);
        home = (EJBHome) obj;
        cache.put(jndiHomeName, home);
      }
      catch (Exception e) {
        throw new ServiceLocatorException(e);
      }
    }
    return home;
  }
  public Object getEJB(String name){
      ServiceConfigBean configBean = (ServiceConfigBean)ctx.getBean(name);
      return configBean.getEjb();
  }

}