DB연결 데이터 입출력(1)

DTO

UserDto.java

package dto;

import java.io.Serializable;

public class UserDto implements Serializable {
	
	private String id;
	private String name;
	private int age;
	private String joindate;
	
	public UserDto() {
	}
	
	public UserDto(String id, String name, int age, String joindate) {
		super();
		this.id = id;
		this.name = name;
		this.age = age;
		this.joindate = joindate;
	}
	
	public String getId() {
		return id;
	}
	public void setId(String id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	public String getJoindate() {
		return joindate;
	}
	public void setJoindate(String joindate) {
		this.joindate = joindate;
	}
	
	@Override
	public String toString() {
		return "UserDto [id=" + id + ", name=" + name + ", age=" + age + ", joindate=" + joindate + "]";
	}

}

---

INSERT

jdbctest.java

package db;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

public class jdbctest {
	
	public jdbctest() {
		
		try {
			Class.forName("oracle.jdbc.driver.OracleDriver"); // 이 클래스가 존재를 하냐 안하냐 할수 있게 해준다.
			
			System.out.println("Driver Loding Success!!");
		} catch (ClassNotFoundException e) {
			
			e.printStackTrace();
		} 
	}
	
	public Connection getConnection() {
		
		Connection conn = null;
		
		try {
			conn = DriverManager.getConnection("jdbc:oracle:thin:@127.0.0.1:1521:xe", "hr", "hr");
			
			System.out.println("DB Connection Success!!");
		} catch (SQLException e) {
			e.printStackTrace();
		}
		
		return conn;
	}
	
	public int Insert(String id, String name, int age) {
		//쿼리문을 작성할땐 앞뒤로 한칸씩 떨어트려 놓자 
		String sql = " INSERT INTO USERDTO(ID, NAME, AGE, JOINDATE) "
				+ " VALUES('" + id + "', '" + name + "', " + age + ", SYSDATE) ";
		
		Connection conn = getConnection(); // db 정보 얻어오기 
		Statement stmt = null;
		
		int count = 0;
		
		System.out.println("sql:" + sql);
		
		try {
			stmt = conn.createStatement();	// db 현상태를 얻어오기
			
			count = stmt.executeUpdate(sql); // sql문을 실행시켜준다.
			
		} catch (SQLException e) {
			e.printStackTrace();
		}finally {
			try {
				if(stmt != null) {
					stmt.close();
				} 
				if(conn != null) {
					conn.close();
				}
			}catch (SQLException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
			}
			
		}
		return count;
	}
	
}

mainClass.java

package main;

import db.jdbctest;
import dto.UserDto;

public class mainClass {

	public static void main(String[] args) {
		/*
			JDBC
			java database connectivity
		 */
		
		jdbctest jt = new jdbctest();
		
		int n = jt.Insert("ddd", "손오천", 21);
		
		if(n > 0){
			System.out.println("정상적으로 추가 되었습니다.");
		}
		
	}

}

---

DELETE

jdbctest.java

public int Delete(String id) {
		//쿼리문을 작성할땐 앞뒤로 한칸씩 떨어트려 놓자 
		String sql = " DELETE FROM USERDTO WHERE ID = '" + id + "'";
				
		
		Connection conn = getConnection(); // db 정보 얻어오기 
		Statement stmt = null;
		
		int count = 0;
		
		System.out.println("sql:" + sql);
		
		try {
			stmt = conn.createStatement();	// db 현상태를 얻어오기
			
			count = stmt.executeUpdate(sql); // sql문을 실행시켜준다.
			
		} catch (SQLException e) {
			e.printStackTrace();
		}finally {
			try {
				if(stmt != null) {
					stmt.close();
				} 
				if(conn != null) {
					conn.close();
				}
			}catch (SQLException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
			}
			
		}
		return count;
	}

mainClass.java

public static void main(String[] args) {
		/*
			JDBC
			java database connectivity
		 */
		
		jdbctest jt = new jdbctest();
		
		int n = jt.Delete("ddd");
		
		if(n > 0){
			System.out.println("정상적으로 삭제 되었습니다.");
		}
}   

---

UPDATE

jdbctest.java

public int Updata(String id, String name, int age) {
		//쿼리문을 작성할땐 앞뒤로 한칸씩 떨어트려 놓자 
		String sql = " UPDATE USERDTO SET NAME = '" + name + "', AGE = " + age
				+ " WHERE ID = '" + id + "'";
				
		
		Connection conn = getConnection(); // db 정보 얻어오기 
		Statement stmt = null;
		
		int count = 0;
		
		System.out.println("sql:" + sql);
		
		try {
			stmt = conn.createStatement();	// db 현상태를 얻어오기
			
			count = stmt.executeUpdate(sql); // sql문을 실행시켜준다.
			
		} catch (SQLException e) {
			e.printStackTrace();
		}finally {
			try {
				if(stmt != null) {
					stmt.close();
				} 
				if(conn != null) {
					conn.close();
				}
			}catch (SQLException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
			}
			
		}
		return count;
	}

mainClass.java

public static void main(String[] args) {
		/*
			JDBC
			java database connectivity
		 */
		
		jdbctest jt = new jdbctest();
		
		int n = jt.Updata("aaa", "손오공", 31);
		
		if(n > 0){
			System.out.println("정상적으로 변경 되었습니다.");
		}
		
	}

---