如何将2进制数转为图片在前端展示?
在制作个人博客的时候遇到的问题,想将数据库(mysql)中的longblob数据类型的数据转为jpg格式的图片展示在前端作为头像,我使用的ssm框架,不知道如何才能做到
结构如下:
重要的程序:
UserDao:
package com.ylq.dao;
import com.ylq.domain.User;
import org.apache.ibatis.annotations.*;
@Mapper
public interface UserDao {
@Select("select * from user where id=#{id}")
public User selectById(long id);
@Insert("insert into user(id,user_name,email,created_time,updated_time,password) values(#{id},#{userName},#{email},#{createdTime},#{updatedTime},#{password})")
public void insertOne(User user);
@UpdateProvider(type = UserSqlProvider.class,method = "updateUser")
public void update(User user);
}
UserServiceImpl:
package com.ylq.service.impl;
import com.ylq.dao.UserDao;
import com.ylq.domain.User;
import com.ylq.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class UserServiceImpl implements UserService {
@Autowired
UserDao userDao;
@Override
public User selectById(long id) {
User user=userDao.selectById(id);
return user;
}
@Override
public void insertOne(User user) {
userDao.insertOne(user);
}
@Override
public void update(User user) {
userDao.update(user);
}
}
domain实体类
package com.ylq.domain;
public class User {
private long id;
private String userName;
private String email;
private String createdTime;
private String updatedTime;
private String password;
private byte[] avatar;
public byte[] getAvatar() {
return avatar;
}
public void setAvatar(byte[] avatar) {
this.avatar = avatar;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", userName='" + userName + '\'' +
", email='" + email + '\'' +
", createdTime='" + createdTime + '\'' +
", updatedTime='" + updatedTime + '\'' +
", password='" + password + '\'' +
", avatar='" + avatar + '\'' +
'}';
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getCreatedTime() {
return createdTime;
}
public void setCreatedTime(String createdTime) {
this.createdTime = createdTime;
}
public String getUpdatedTime() {
return updatedTime;
}
public void setUpdatedTime(String updatedTime) {
this.updatedTime = updatedTime;
}
}
数据库: