jdbcprovider.java

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/*
 * Created on Jul 11, 2003
 *
 * To change the template for this generated file go to
 * Window>Preferences>Java>Code Generation>Code and Comments
 */
package ar.com.koalas.providers;

import java.lang.reflect.InvocationTargetException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Collection;
import java.util.Hashtable;
import java.util.Map;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;

import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.collections.Closure;
import org.apache.commons.collections.CollectionUtils;
import org.apache.commons.collections.Transformer;
import org.apache.commons.dbutils.handlers.MapListHandler;

/**
 * @author DZ156H
 *
 * To change the template for this generated type comment go to
 * Window>Preferences>Java>Code Generation>Code and Comments
 */
public class JDBCProvider extends ProviderImpl {
	private static final String PARAM_QUERY = "query";
	
	private String jndi;
	private String initialContext;
	
	private String keyName;
	private String description;
	private Collection cachedCollection;
	private boolean isCached = false;
	
	private String beanFactoryName = Map2DynaBeanFactory.class.getName();
	
	private Map localIndex = null;

	public Collection getCollection() throws ProviderException {
		try {
			if( this.cachedCollection == null || !this.isCached ){
				this.isCached = true;
				this.cachedCollection = this.executeQuery();
			}
			
			return this.cachedCollection;
		} catch (Exception e) {
			e.printStackTrace();
			throw new ProviderException( e );
		}
	}
	

	public Object getDescription(Object id) throws ProviderException {
		this.getCollection();
		return this.localIndex.get(id.toString());
	}	

	public String getJndi() {
		return jndi;
	}

	public void setJndi(String string) {
		jndi = string;
	}

	public String getDescription() {
		return description;
	}

	public String getKeyName() {
		return keyName;
	}

	public void setDescription(String string) {
		description = string;
	}

	public void setKeyName(String string) {
		keyName = string;
	}
	
	private Collection executeQuery() throws NamingException, SQLException, InvocationTargetException, NoSuchMethodException, IllegalAccessException, InstantiationException, ClassNotFoundException{
		Context initialContext = new InitialContext();
		Context envCtx = (Context) initialContext.lookup( this.initialContext );
		DataSource ds = (DataSource)envCtx.lookup( this.jndi );
		
		Connection con = ds.getConnection();
		PreparedStatement ps = con.prepareStatement( this.getParam(PARAM_QUERY) );
		ResultSet rs = ps.executeQuery();		
		try{
			return this.rsToCollection( rs );
		}catch( Throwable t ){
		    t.printStackTrace();
		    return null;
		}finally{
			rs.close();
			ps.close();
			con.close();
		}
	}

	private Collection rsToCollection(ResultSet rs) throws SQLException, InvocationTargetException, NoSuchMethodException, IllegalAccessException, InstantiationException, ClassNotFoundException {
		Collection retValue = (Collection) new MapListHandler().handle(rs);
		retValue = CollectionUtils.collect( retValue, new Transformer(){
            public Object transform(Object arg) {
                return JDBCProvider.this.getBeanFactory().create(arg);
            }} );
		
		this.localIndex = new Hashtable();

		CollectionUtils.forAllDo( retValue, new Closure(){
            public void execute(Object arg) {
                try {
                    JDBCProvider.this.localIndex.put(BeanUtils.getProperty(arg, JDBCProvider.this.getKeyName()), BeanUtils.getProperty(arg, JDBCProvider.this.getDescription()));
                } catch (IllegalAccessException e) {
                    e.printStackTrace();
                } catch (InvocationTargetException e) {
                    e.printStackTrace();
                } catch (NoSuchMethodException e) {
                    e.printStackTrace();
                }
            }} );
	
		return retValue;
	}

	private BeanFactory getBeanFactory() {
		if( this.beanFactoryName != null ){
			try {
				return (BeanFactory) Class.forName( this.getBeanFactoryName() ).newInstance();
			} catch (InstantiationException e) {
			} catch (IllegalAccessException e) {
			} catch (ClassNotFoundException e) {
			}
		}
		return null;
	}


	public String getBeanFactoryName() {
		return beanFactoryName;
	}

	public void setBeanFactoryName(String string) {
		beanFactoryName = string;
	}

    public String getInitialContext() {
        return initialContext;
    }

    public void setInitialContext(String initialContext) {
        this.initialContext = initialContext;
    }
}