agencybean.java

21天学学会J2EE的源码1 是一本非常不错的书

			stmt.setString(1, name);
			stmt.setString(2, description);
			stmt.executeUpdate();
		}
        catch (SQLException e) {
            error("Error creating Location "+name,e);
		}
        finally {
            closeConnection(con, stmt, null);
        }
	}

	public void removeLocation(String code) throws NotFoundException {
        Connection con = null;
        PreparedStatement stmt = null;
        try {
            con = dataSource.getConnection();
            stmt = con.prepareStatement(
            "UPDATE Job SET location = '' WHERE location = ?");

            stmt.setString(1, code);
            stmt.executeUpdate();

            stmt = con.prepareStatement(
            "UPDATE Applicant SET location = '' WHERE location = ?");

            stmt.setString(1, code);
            stmt.executeUpdate();

            stmt = con.prepareStatement(
            "DELETE FROM Location WHERE name = ?");

            stmt.setString(1, code);
            stmt.executeUpdate();
        }
        catch (SQLException e) {
            error("Error removing Location "+code,e);
		}
        finally {
            closeConnection(con, stmt, null);
        }
	}

	public Collection getSkills() {
        Connection con = null;
        PreparedStatement stmt = null;
        ResultSet rs = null;
        try {
            con = dataSource.getConnection();
            stmt = con.prepareStatement(
            "SELECT name FROM Skill");

            rs = stmt.executeQuery();

            Collection col = new TreeSet();
            while (rs.next()) {
                col.add(rs.getString(1));
            }

            return col;
        }
        catch (SQLException e) {
            error("Error getting Skill list: ",e);
		}
        finally {
            closeConnection(con, stmt, rs);
        }
        return null;
	}

	public String getSkillDescription(String name) throws NotFoundException {
        Connection con = null;
        PreparedStatement stmt = null;
        ResultSet rs = null;
        try {
            con = dataSource.getConnection();
            stmt = con.prepareStatement(
            "SELECT description FROM Skill WHERE name = ?");

			stmt.setString(1, name);
            rs = stmt.executeQuery();

            if (!rs.next()) {
            	throw new NotFoundException("Unknown skill: "+name);
            }
            return rs.getString(1);
        }
        catch (SQLException e) {
            error("Error getting skill description for "+name,e);
		}
        finally {
            closeConnection(con, stmt, rs);
        }
        return null;
	}

	public void updateSkill(String name, String description) throws NotFoundException {
        Connection con = null;
        PreparedStatement stmt = null;
        try {
            con = dataSource.getConnection();
            stmt = con.prepareStatement(
            "UPDATE Skill SET description = ? WHERE name = ?");

			stmt.setString(1, description);
			stmt.setString(2, name);
            stmt.executeUpdate();
        }
        catch (SQLException e) {
            error("Error updating Skill: "+name,e);
		}
        finally {
            closeConnection(con, stmt, null);
        }
	}

	public void addSkill (String name, String description) throws DuplicateException {
		Collection skills = getSkills();
		Iterator it = skills.iterator();
		while (it.hasNext()) {
			String s = (String)it.next();
			if (s.equalsIgnoreCase(name))
				throw (new DuplicateException(s+" skill already defined"));
		}

        Connection con = null;
        PreparedStatement stmt = null;
        try {
			con = dataSource.getConnection();
			stmt = con.prepareStatement(
			"INSERT INTO Skill (name,description) VALUES (?,?)");

			stmt.setString(1, name);
			stmt.setString(2, description);
			stmt.executeUpdate();
		}
        catch (SQLException e) {
            error("Error creating skill "+name,e);
		}
        finally {
            closeConnection(con, stmt, null);
        }
	}

	public void removeSkill (String name) throws NotFoundException {
        Connection con = null;
        PreparedStatement stmt = null;
        try {
            con = dataSource.getConnection();
            stmt = con.prepareStatement(
            "DELETE FROM JobSkill WHERE skill = ?");

            stmt.setString(1, name);
            stmt.executeUpdate();

            stmt = con.prepareStatement(
            "DELETE FROM ApplicantSkill WHERE skill = ?");

            stmt.setString(1, name);
            stmt.executeUpdate();

            stmt = con.prepareStatement(
            "DELETE FROM Skill WHERE name = ?");

            stmt.setString(1, name);
            stmt.executeUpdate();
        }
        catch (SQLException e) {
            error("Error deleting skill "+name,e);
        }
        finally {
            closeConnection(con, stmt, null);
        }
	}

	public List select(String table) {
        Connection con = null;
        PreparedStatement stmt = null;
        ResultSet rs = null;
        try {
            con = dataSource.getConnection();
            stmt = con.prepareStatement(
            "SELECT * FROM "+table);

            rs = stmt.executeQuery();
            ResultSetMetaData rsmd = rs.getMetaData();
            int numCols = rsmd.getColumnCount();

            List ans = new ArrayList();
            String[] hdr = new String[numCols];

            // get column header info
            for (int i=1; i <= numCols; i++)
                hdr[i-1] = rsmd.getColumnLabel(i);
            ans.add(hdr);

            while (rs.next()) {
            	String[] row = new String[numCols];
          		for (int i=1; i <= numCols; i++)
					row[i-1] = rs.getString(i);
				ans.add(row);
            }

            return ans;
        }
        catch (SQLException e) {
            error("Error getting table rows",e);
		}
        finally {
            closeConnection(con, stmt, rs);
        }
        return null;
	}

    private void closeConnection (Connection con, PreparedStatement stmt, ResultSet rslt) {
        if (rslt != null) {
            try {
                rslt.close();
            }
            catch (SQLException e) {}
        }
        if (stmt != null) {
            try {
                stmt.close();
            }
            catch (SQLException e) {}
        }
        if (con != null) {
            try {
                con.close();
            }
            catch (SQLException e) {}
        }
    }

	// EJB methods start here

	private void error (String msg, Exception ex) {
		String s = "AgencyBean: "+msg + "\n" + ex;
        System.out.println(s);
        throw new EJBException(s,ex);
	}

	public void ejbCreate () throws CreateException {
        InitialContext ic = null;
        try {
	        ic = new InitialContext();
	        dataSource = (DataSource)ic.lookup("java:comp/env/jdbc/Agency");
        }
        catch (NamingException ex) {
            error("Error connecting to java:comp/env/jdbc/Agency:",ex);
            return;
        }
        try {
	        name = (String)ic.lookup("java:comp/env/AgencyName");
        }
        catch (NamingException ex) {
            error("Error looking up java:comp/env/AgencyName:",ex);
        }
	}

    public void ejbActivate(){
    }

    public void ejbPassivate(){
    }

    public void ejbRemove(){
    	dataSource = null;
    }

    private SessionContext ctx;

    public void setSessionContext(SessionContext ctx) {
		this.ctx = ctx;
    }
}