コンパイルエラーについて

関連ファイル
package jspbean;

import java.sql.*;
import java.util.ArrayList;

public class EmployeeDAO{
   private final static String DRIVER_URL =
   "jdbc:mysql://localhost:3306/examdb?useUnicode=true&characterEncoding=Windows-31J";
   private final static String DRIVER_NAME = "com.mysql.jdbc.Driver";
   private final static String USER_NAME = "root";
   private final static String PASSWORD = "";
   
   protected Connection createConnection () {
     try {
        Class.forName(DRIVER_NAME);
        Connection con = DriverManager.getConnection(DRIVER_URL,USER_NAME,PASSWORD);
        return con;  
     } catch( ClassNotFoundException e ) {
        System.out.println("Can't Find JDBC Driver.\n");
     } catch( SQLException e ) {
        System.out.println("Connect Error.\n");
     }
      return null;
    }

   protected void closeConnection( Connection con ) {
      try {
         con.close( );
      } catch( Exception ex ) { }
   }
   
   public ArrayList findAll(){
      ArrayList list = new ArrayList();
      Connection con = null;
      try{
         con = createConnection();
         String sql = "select * from employee inner join department using(dep_id) order by number";
         Statement stmt = con.createStatement();
         ResultSet rs = stmt.executeQuery(sql);         
         while(rs.next()){
            int number = rs.getInt("number");
            String name = rs.getString("name");
            int age = rs.getInt("age");
            int depID = rs.getInt("dep_id");
            String depName = rs.getString("dep_name");
            list.add(new Employee(number, name, age, depID, depName));
         }
         stmt.close();
         rs.close();                 
         return list;
      }catch(SQLException e){
         e.printStackTrace();   
         return null;
      }finally{
         closeConnection(con);
      }
   }

   public void create(Employee emp){
      Connection con = null;
      try{
         con = createConnection();
         String sql ="insert into employee values(?, ?, ?, ?)";
         PreparedStatement stmt = con.prepareStatement(sql);
         stmt.setInt(1, emp.getNumber());
         stmt.setString(2, emp.getName());
         stmt.setInt(3, emp.getAge());
         stmt.setInt(4, emp.getDepID());           
         stmt.executeUpdate();
      }catch(SQLException e){
         System.err.println("従業員の追加失敗");
         e.printStackTrace();
      }finally{
         closeConnection(con);   
      }
   }

  public int store(Employee emp){
    Connection con = null;
    int updated = 0;
    try{
      con = createConnection();
      int number = emp.getNumber();
      int dep_id = emp.getDepID();
      String sql ="update employee set dep_id="
                 + dep_id + " where number=" + number;
      Statement stmt = con.createStatement();
      updated = stmt.executeUpdate(sql);
      return updated;
    }catch(SQLException e){
      System.out.println("従業員テーブルの更新失敗");
      e.printStackTrace();
      return -1;
    }finally{
      closeConnection(con);   
    }
  }   
}

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関連ファイル
package jspbean;

public class Employee {
    private int mNumber;
    private String mName;
    private int mAge;
    private int mDepID;
    private String mDepName;
    
    public Employee(int number, String name, int age,
                     int depID, String depName){
        this.mNumber = number;
        this.mName = name;
        this.mAge = age;
        this.mDepID = depID;
        this.mDepName = depName;
    }

    public Employee(){
    }
    
    public int getNumber() {return mNumber;}
    public void setNumber(int i) {mNumber = i;}

    public String getName() {return mName;}
    public void setName(String string) {mName = string;}

    public int getAge() {return mAge;}
    public void setAge(int i) {mAge = i;}

    public int getDepID() {return mDepID;}
    public void setDepID(int i) {mDepID = i;}

    public String getDepName() {return mDepName;}
    public void setDepName(String string) {mDepName = string;}
}