java mysql增删改查

以下是Java中使用MySQL进行增删改查的示例代码：

### 增加数据

public void addStudent(Student student) {
    try {
        Connection conn = getConnection();
        String sql = "INSERT INTO student(name, age, gender) VALUES(?, ?, ?)";
        PreparedStatement pstmt = conn.prepareStatement(sql);
        pstmt.setString(1, student.getName());
        pstmt.setInt(2, student.getAge());
        pstmt.setString(3, student.getGender());
        pstmt.executeUpdate();
        pstmt.close();
        conn.close();
    } catch (SQLException e) {
        e.printStackTrace();
    }
}

### 删除数据

public void deleteStudent(int id) {
    try {
        Connection conn = getConnection();
        String sql = "DELETE FROM student WHERE id=?";
        PreparedStatement pstmt = conn.prepareStatement(sql);
        pstmt.setInt(1, id);
        pstmt.executeUpdate();
        pstmt.close();
        conn.close();
    } catch (SQLException e) {
        e.printStackTrace();
    }
}

### 修改数据

public void updateStudent(Student student) {
    try {
        Connection conn = getConnection();
        String sql = "UPDATE student SET name=?, age=?, gender=? WHERE id=?";
        PreparedStatement pstmt = conn.prepareStatement(sql);
        pstmt.setString(1, student.getName());
        pstmt.setInt(2, student.getAge());
        pstmt.setString(3, student.getGender());
        pstmt.setInt(4, student.getId());
        pstmt.executeUpdate();
        pstmt.close();
        conn.close();
    } catch (SQLException e) {
        e.printStackTrace();
    }
}

### 查询数据

public List<Student> findAllStudents() {
    List<Student> students = new ArrayList<Student>();
    try {
        Connection conn = getConnection();
        String sql = "SELECT * FROM student";
        PreparedStatement pstmt = conn.prepareStatement(sql);
        ResultSet rs = pstmt.executeQuery();
        while (rs.next()) {
            Student student = new Student();
            student.setId(rs.getInt("id"));
            student.setName(rs.getString("name"));
            student.setAge(rs.getInt("age"));
            student.setGender(rs.getString("gender"));
            students.add(student);
        }
        rs.close();
        pstmt.close();
        conn.close();
    } catch (SQLException e) {
        e.printStackTrace();
    }
    return students;
}

以上是Java中使用MySQL进行增删改查的示例代码，其中Student为一个Java Bean类，包含id、name、age、gender等属性。具体实现需要根据实际情况进行调整。