projectdaoimpl.java

J2EE & Tomcat books published by hope

/*
 */

package com.sun.j2ee.workflow.project.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;

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

import com.sun.j2ee.workflow.util.JNDINames;
import com.sun.j2ee.workflow.project.dao.ProjectDAO;
import com.sun.j2ee.workflow.util.DatabaseNames;
import com.sun.j2ee.workflow.project.model.ProjectModel;

import com.sun.j2ee.workflow.project.exceptions.ProjectDAOSysException;
import com.sun.j2ee.workflow.project.exceptions.ProjectDAOAppException;
import com.sun.j2ee.workflow.project.exceptions.ProjectDAODBUpdateException;
import com.sun.j2ee.workflow.project.exceptions.ProjectDAOFinderException;
import com.sun.j2ee.workflow.project.exceptions.ProjectDAODupKeyException;

import com.sun.j2ee.workflow.util.Debug;

/** This class calls the simple Datasource from Tomcat to get connection
 * No connection pooling is used.
 * @author Jian (James) Cai
 */
public class ProjectDAOImpl implements ProjectDAO {
    
    private transient Connection dbConnection = null;
    private transient DataSource datasource   = null;
    
    public ProjectDAOImpl() throws ProjectDAOSysException {
        try {
            InitialContext ic = new InitialContext();
            datasource = (DataSource) ic.lookup(JNDINames.WORKFLOW_DATASOURCE);
        } catch (NamingException ne) {
            throw new ProjectDAOSysException("Naming Exception while looking "
            + " up DataSource Connection " +
            JNDINames.WORKFLOW_DATASOURCE +
            ": \n" + ne.getMessage());
        }
    }
/*
    public void query{
 
        // load the PoolMan JDBC Driver
        try {
            Class.forName("com.codestudio.sql.PoolMan").newInstance();
        } catch (Exception ex) {
            System.out.println("Could Not Find the PoolMan Driver. " +
                               "Is poolman.jar in your CLASSPATH?");
            System.exit(0);
        }
 
        // establish a Connection to the last database listed in the 'poolman.props' file
        Connection con = DriverManager.getConnection("jdbc:poolman");
 
        try {
 
            Statement s = con.createStatement();
            ResultSet res = s.executeQuery(sql);
            ResultSetMetaData meta = res.getMetaData();
 
            int cols = meta.getColumnCount();
            while (res.next()) {
                for (int i = 1; i <= cols; i++) {
                    Object val = res.getObject(i);
                    System.out.print("\t" + meta.getColumnLabel(i) + ": ");
                    System.out.print(val == null ? " " : val.toString());
                }
                System.out.print("\n");
            }
        } catch (SQLException sqe) {
        }
        finally {
            // this close method merely returns the Connection to the pool
            // after implicitly closing related resources (Statements and ResultSets)
            con.close();
            System.out.println("SAMPLE: Closed Con");
        }
 
 
    }
 */
    public void create(ProjectModel projectinfo) throws ProjectDAOSysException,
    ProjectDAODupKeyException,
    ProjectDAODBUpdateException,
    ProjectDAOAppException {
        insertproject(projectinfo);
    }
    
    public ProjectModel load(String id) throws ProjectDAOSysException,
    ProjectDAOFinderException {
        return(selectproject(id));
    }
    
    public void store(ProjectModel projectinfo) throws ProjectDAODBUpdateException,
    ProjectDAOAppException,
    ProjectDAOSysException  {
        updateproject(projectinfo);
    }
    
    public void remove(String id) throws ProjectDAODBUpdateException,
    ProjectDAOSysException {
        deleteproject(id);
    }
    
    public String findByPrimaryKey(String projectId) throws
    ProjectDAOFinderException,
    ProjectDAOSysException {
        if (projectExists(projectId))
            return (projectId);
        throw new ProjectDAOFinderException("primary key not found :"+projectId);
    }
    
    public Collection findByName(String project_name) throws
    ProjectDAOFinderException,
    ProjectDAOSysException {
        PreparedStatement stmt = null;
        ResultSet result = null;
        ProjectModel pmodel = null;
        boolean returnValue = false;
        ArrayList results = new ArrayList();
        String queryStr ="SELECT * FROM " +
        DatabaseNames.PROJECT_TABLE
        + " WHERE proj_name = " + "'" + project_name.trim() + "'";
        Debug.println("queryString is: "+ queryStr);
        
        try {
            getDBConnection();
            stmt = createPreparedStatement(dbConnection, queryStr);
            result = stmt.executeQuery();
            while(result.next()) {
                pmodel = new ProjectModel(result.getString(1),result.getString(2),result.getString(3),result.getString(4),result.getString(5));
                results.add(pmodel);
            }
        } catch(SQLException se) {
            throw new ProjectDAOSysException(
            "SQLException while selecting"
            + " existing project - name -> " + project_name + " :\n" + se);
        } finally {
            closeResultSet(result);
            closeStatement(stmt);
            closeConnection();
        }
        return (results);
    }
    
    public Collection findAll() throws
    ProjectDAOFinderException,
    ProjectDAOSysException {
        PreparedStatement stmt = null;
        ResultSet result = null;
        ProjectModel pmodel = null;
        boolean returnValue = false;
        ArrayList results = new ArrayList();
        String queryStr ="SELECT * FROM " +
        DatabaseNames.PROJECT_TABLE;
        Debug.println("queryString is: "+ queryStr);
        try {
            getDBConnection();
            stmt = createPreparedStatement(dbConnection, queryStr);
            result = stmt.executeQuery();
            while(result.next()) {
                pmodel = new ProjectModel(result.getString(1),result.getString(2),result.getString(3),result.getString(4),result.getString(5));
                results.add(pmodel);
            }
        } catch(SQLException se) {
            throw new ProjectDAOSysException(
            "SQLException while selecting"
            + " existing all project  -> "  + " :\n" + se);
        } finally {
            closeResultSet(result);
            closeStatement(stmt);
            closeConnection();
        }
        return (results);
    }
    
    private boolean projectExists(String projectId) throws ProjectDAOSysException {
        PreparedStatement stmt = null;
        ResultSet result = null;
        boolean returnValue = false;
        String queryStr ="SELECT proj_ID FROM " +
        DatabaseNames.PROJECT_TABLE
        + " WHERE proj_ID = " + "'" + projectId.trim() + "'";
        Debug.println("queryString is: "+ queryStr);
        
        try {
            getDBConnection();
            stmt = createPreparedStatement(dbConnection, queryStr);
            result = stmt.executeQuery();
            if ( !result.next() ) {
                returnValue = false;
            } else {
                projectId = result.getString(1);
                returnValue = true;
            }
        } catch(SQLException se) {
            throw new ProjectDAOSysException(
            "SQLException while checking for an"
            + " existing project - id -> " + projectId + " :\n" + se);
        } finally {
            closeResultSet(result);
            closeStatement(stmt);
            closeConnection();
        }
        return returnValue;
    }
    
    private boolean isValidData(ProjectModel projectinfo) {
        if (
        (projectinfo.getProj_name() == null) ||
        (projectinfo.getGroup() == null) )
            return (false);
        else
            return (true);
    }
    
    private void insertproject(ProjectModel projectinfo) throws
    ProjectDAOSysException,
    ProjectDAODupKeyException,
    ProjectDAODBUpdateException,
    ProjectDAOAppException {
        
        if (!isValidData(projectinfo))
            throw new ProjectDAOAppException("Illegal data values for insert");
        String generatedID = generateID();
        if (projectExists(generatedID))
            throw new ProjectDAODupKeyException("project exists for "+
            projectinfo.getProj_ID());
        
        PreparedStatement stmt = null;
        String queryStr = "INSERT INTO " + DatabaseNames.PROJECT_TABLE
        + "(proj_ID, proj_name, group, lead, desc) "
        + "VALUES ("
        + "'" + generatedID + "',"
        + "'" + projectinfo.getProj_name().trim() + "',"
        + "'" + projectinfo.getGroup().trim() + "',"
        + "'" + projectinfo.getLead().trim() + "',"