文章目录
SpringBoot+JdbcTemplate通用Mapper的实现通用Mapper针对User的jdbcMapper针对 User的Service相应的Controller
SpringBoot+JdbcTemplate通用Mapper的实现
就我个人而言, 使用某个框架, 还是建议尽是只使用框架原生提供的方法来完成相关的操作, 这样从各方面来说应该都是性能最优的. 代码也应该是最好阅读和理解的. 这里还用上一篇中的model来说明. 各位也可以对两篇进行一下对比, 看看哪一种更适合你.
通用Mapper
package cn
.miw
.rpc
.jdbc
.common
;
import java
.lang
.reflect
.Field
;
import java
.lang
.reflect
.ParameterizedType
;
import java
.sql
.ResultSet
;
import java
.sql
.SQLException
;
import java
.util
.ArrayList
;
import java
.util
.List
;
import org
.springframework
.beans
.factory
.annotation
.Autowired
;
import org
.springframework
.jdbc
.core
.JdbcTemplate
;
import org
.springframework
.jdbc
.core
.RowMapper
;
public abstract class GernalRowMapper<T
extends BaseEntity> implements RowMapper<T> {
@Autowired
protected JdbcTemplate jdbcTemplate
;
@SuppressWarnings("unchecked")
@Override
public T
mapRow(ResultSet rs
, int rowNum
) throws SQLException
{
Object instance
= null
;
Class
<?> clz
= getTrueClass();
try {
instance
= clz
.newInstance();
Field
[] fields
= clz
.getDeclaredFields();
for (Field field
: fields
) {
field
.setAccessible(true);
field
.set(instance
, rs
.getObject(field
.getName()));
}
} catch (InstantiationException | IllegalAccessException e
) {
}
return (T
) instance
;
}
private Class
<T> getTrueClass() {
ParameterizedType type
= (ParameterizedType
) this.getClass().getGenericSuperclass();
@SuppressWarnings("unchecked")
Class
<T> clazz
= (Class
<T>) type
.getActualTypeArguments()[0];
return clazz
;
}
public List
<T> list(String sql
, Object
... args
) {
return jdbcTemplate
.query(sql
, this, args
);
}
public T
find(String sql
, Object
... args
) {
return jdbcTemplate
.queryForObject(sql
, this, args
);
}
public void save(T object
) {
String sql
= "insert into " + object
.getClass().getSimpleName();
Field
[] fields
= object
.getClass().getDeclaredFields();
List
<String> f
= new ArrayList<String>();
List
<String> v
= new ArrayList<String>();
for (Field field
: fields
) {
field
.setAccessible(true);
try {
Object value
= field
.get(object
);
if (value
!= null
) {
f
.add(field
.getName());
v
.add("'" + value
.toString() + "'");
}
} catch (IllegalArgumentException | IllegalAccessException e
) {
}
}
sql
+= "(" + StringUtils
.join(f
) + ") values(" + StringUtils
.join(v
) + ")";
jdbcTemplate
.execute(sql
);
}
public void del(T object
) {
String sql
= "delete from " + object
.getClass().getSimpleName() + " where 1=1";
Field
[] fields
= object
.getClass().getDeclaredFields();
for (Field field
: fields
) {
field
.setAccessible(true);
try {
Object value
= field
.get(object
);
if (value
!= null
) {
if (value
instanceof String && ((String
) value
).contains("%")) {
sql
+= " and " + field
.getName() + " like '" + value
.toString() + "'";
} else {
sql
+= " and " + field
.getName() + " = '" + value
.toString() + "'";
}
}
} catch (IllegalArgumentException | IllegalAccessException e
) {
}
}
jdbcTemplate
.execute(sql
);
}
public int update(T object
) {
String sql
= "update " + object
.getClass().getSimpleName();
String id
= "";
List
<String> list
= new ArrayList<>();
Field
[] fields
= object
.getClass().getDeclaredFields();
for (Field field
: fields
) {
field
.setAccessible(true);
try {
Object value
= field
.get(object
);
if ("id".equals(field
.getName())) {
id
= value
.toString();
} else {
list
.add(field
.getName() + " = " + (value
== null
? "NULL" : "'" + value
.toString() + "'"));
}
} catch (IllegalArgumentException | IllegalAccessException e
) {
}
}
sql
+= " set " + StringUtils
.join(list
) + " where id=" + id
;
return jdbcTemplate
.update(sql
);
}
public List
<T> page(T object
) {
String sql
= "select * from " + object
.getClass().getSimpleName() + " where 1=1";
Field
[] fields
= object
.getClass().getDeclaredFields();
for (Field field
: fields
) {
field
.setAccessible(true);
try {
Object value
= field
.get(object
);
if (value
!= null
) {
if (value
instanceof String && ((String
) value
).contains("%")) {
sql
+= " and " + field
.getName() + " like '" + value
.toString() + "'";
} else {
sql
+= " and " + field
.getName() + " = '" + value
.toString() + "'";
}
}
} catch (IllegalArgumentException | IllegalAccessException e
) {
}
}
sql
+= " limit " + object
.getStart() + "," + object
.getPageSize();
return jdbcTemplate
.query(sql
, this);
}
}
针对User的jdbcMapper
package cn
.miw
.rpc
.jdbc
.mapper
;
import org
.springframework
.stereotype
.Repository
;
import cn
.miw
.rpc
.jdbc
.common
.GernalRowMapper
;
import cn
.miw
.rpc
.jdbc
.model
.User
;
@Repository
public class UserMapper extends GernalRowMapper<User>{
}
就这样简单, 其实什么也不用写了
针对 User的Service
package cn
.miw
.rpc
.jdbc
.service
;
import java
.util
.List
;
import org
.springframework
.beans
.factory
.annotation
.Autowired
;
import org
.springframework
.stereotype
.Service
;
import cn
.miw
.rpc
.jdbc
.mapper
.UserMapper
;
import cn
.miw
.rpc
.jdbc
.model
.User
;
@Service
public class UserService {
@Autowired
private UserMapper mapper
;
public List
<User> list(){
String sql
= "select * from User where name like ? ";
List
<User> list
= mapper
.list(sql
,"%");
return list
;
}
public List
<User> list(int page
,int pageSize
){
String sql
= "select * from User where name like ? limit "+((page
-1)*pageSize
)+","+pageSize
;
List
<User> list
= mapper
.list(sql
,"%");
return list
;
}
public List
<User> page(int page
,int pageSize
){
User object
=new User();
object
.setPage(page
);
List
<User> list
= mapper
.page(object
);
return list
;
}
public User
find(int id
) {
String sql
= "select * from User where id=?";
return mapper
.find(sql
, id
);
}
public void save(User user
) {
mapper
.save(user
);
}
public void del(User user
) {
mapper
.del(user
);
}
public void update(User user
) {
mapper
.update(user
);
}
}
相应的Controller
package cn
.miw
.rpc
.jdbc
;
import java
.util
.ArrayList
;
import java
.util
.List
;
import java
.util
.concurrent
.Callable
;
import java
.util
.concurrent
.ExecutorService
;
import java
.util
.concurrent
.Executors
;
import org
.springframework
.beans
.factory
.annotation
.Autowired
;
import org
.springframework
.web
.bind
.annotation
.GetMapping
;
import org
.springframework
.web
.bind
.annotation
.PathVariable
;
import org
.springframework
.web
.bind
.annotation
.PostMapping
;
import org
.springframework
.web
.bind
.annotation
.RequestBody
;
import org
.springframework
.web
.bind
.annotation
.RestController
;
import org
.springframework
.web
.client
.RestTemplate
;
import cn
.miw
.rpc
.batis
.common
.JSON
;
import cn
.miw
.rpc
.jdbc
.model
.MovieInfo
;
import cn
.miw
.rpc
.jdbc
.model
.User
;
import cn
.miw
.rpc
.jdbc
.service
.UserService
;
import io
.swagger
.annotations
.Api
;
@Api
@RestController
public class IndexController {
@Autowired
private UserService service
;
@GetMapping("/")
public List
<User> index() {
List
<User> list
= service
.page(1, 5);
return list
;
}
@GetMapping("/add")
public void add() {
User user
=new User();
user
.setAge(50);
user
.setName("赵钱孙");
service
.save(user
);
}
@GetMapping("/del")
public void del() {
User user
=new User();
user
.setAge(50);
user
.setName("赵钱孙");
service
.del(user
);
}
@GetMapping("/update")
public void update() {
User user
=new User();
user
.setId(13);
user
.setAge(52);
user
.setName("赵钱孙");
service
.update(user
);
}
@GetMapping("/user/{id}")
public User
user(@PathVariable int id
) {
User list
= service
.find(id
);
return list
;
}
}
与 Mybatis的使用一样, 同样非常的简单, 但不用引入更多的东西.
原文发表在 https://www.miw.cn/2018/10/25/springboot-jdbctemplate-tong-yong-mapper-de-shi-xian/
