本文演示了springboot下,实用spring-data-jpa来实现crud操作，视图层采用freemarker
这里我们先把application.properties修改成application.yml 主流格式
内容也改成yml规范格式：
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
|
server:
port: 8888
context-path: /
helloworld: spring boot\u4f60\u597d
msyql:
jdbcname: com.mysql.jdbc.driver
dburl: jdbc:mysql://localhost:3306/db_diary
username: root
password: 123456
spring:
datasource:
driver-class-name: com.mysql.jdbc.driver
url: jdbc:mysql://localhost:3306/db_book
username: root
password: passwd
jpa:
hibernate.ddl-auto: update
show-sql: true
|
yml格式有个注意点 冒号后面一定要加个空格
还有我们把context-path改成/方便开发应用
先写一个bookdao接口
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
|
package com.hik.dao;
import org.springframework.data.jpa.repository.jparepository;
import com.hik.entity.book;
/**
* 图书dao接口
* @author jed
*
*/
public interface bookdao extends jparepository<book, integer>{
}
|
要求实现jparepository，jparepository是继承pagingandsortingrepository，pagingandsortingrepository是继承crudrepository。crudrepository实现了实体增删改查操作
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
|
/*
* copyright 2008-2011 the original author or authors.
*
* licensed under the apache license, version 2.0 (the "license");
* you may not use this file except in compliance with the license.
* you may obtain a copy of the license at
*
* http://www.apache.org/licenses/license-2.0
*
* unless required by applicable law or agreed to in writing, software
* distributed under the license is distributed on an "as is" basis,
* without warranties or conditions of any kind, either express or implied.
* see the license for the specific language governing permissions and
* limitations under the license.
*/
package org.springframework.data.repository;
import java.io.serializable;
/**
* interface for generic crud operations on a repository for a specific type.
*
* @author oliver gierke
* @author eberhard wolff
*/
@norepositorybean
public interface crudrepository<t, id extends serializable> extends repository<t, id> {
/**
* saves a given entity. use the returned instance for further operations as the save operation might have changed the
* entity instance completely.
*
* @param entity
* @return the saved entity
*/
<s extends t> s save(s entity);
/**
* saves all given entities.
*
* @param entities
* @return the saved entities
* @throws illegalargumentexception in case the given entity is {@literal null}.
*/
<s extends t> iterable<s> save(iterable<s> entities);
/**
* retrieves an entity by its id.
*
* @param id must not be {@literal null}.
* @return the entity with the given id or {@literal null} if none found
* @throws illegalargumentexception if {@code id} is {@literal null}
*/
t findone(id id);
/**
* returns whether an entity with the given id exists.
*
* @param id must not be {@literal null}.
* @return true if an entity with the given id exists, {@literal false} otherwise
* @throws illegalargumentexception if {@code id} is {@literal null}
*/
boolean exists(id id);
/**
* returns all instances of the type.
*
* @return all entities
*/
iterable<t> findall();
/**
* returns all instances of the type with the given ids.
*
* @param ids
* @return
*/
iterable<t> findall(iterable<id> ids);
/**
* returns the number of entities available.
*
* @return the number of entities
*/
long count();
/**
* deletes the entity with the given id.
*
* @param id must not be {@literal null}.
* @throws illegalargumentexception in case the given {@code id} is {@literal null}
*/
void delete(id id);
/**
* deletes a given entity.
*
* @param entity
* @throws illegalargumentexception in case the given entity is {@literal null}.
*/
void delete(t entity);
/**
* deletes the given entities.
*
* @param entities
* @throws illegalargumentexception in case the given {@link iterable} is {@literal null}.
*/
void delete(iterable<? extends t> entities);
/**
* deletes all entities managed by the repository.
*/
void deleteall();
}
|
再写一个bookcontroller类
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
|
package com.hik.controller;
import javax.annotation.resource;
import org.springframework.stereotype.controller;
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.requestmapping;
import org.springframework.web.bind.annotation.requestmethod;
import org.springframework.web.servlet.modelandview;
import com.hik.dao.bookdao;
import com.hik.entity.book;
/**
* book控制类
* @author jed
*
*/
@controller
@requestmapping("/book")
public class bookcontroller {
@resource
private bookdao bookdao;
/**
* 查询所有图书
* @return
*/
@requestmapping(value="/list")
public modelandview list() {
modelandview mav = new modelandview ();
mav.addobject("booklist", bookdao.findall());
mav.setviewname("booklist");
return mav;
}
/**
* 添加图书
* @param book
* @return
*/
@requestmapping(value="/add", method=requestmethod.post)
public string add(book book) {
bookdao.save(book);
return "forward:/book/list";
}
@getmapping(value="/preupdate/{id}")
public modelandview preupdate(@pathvariable("id") integer id) {
modelandview mav = new modelandview();
mav.addobject("book", bookdao.getone(id));
mav.setviewname("bookupdate");
return mav;
}
/**
* 修改图书
* @param book
* @return
*/
@postmapping(value="/update")
public string update(book book) {
bookdao.save(book);
return "forward:/book/list";
}
/**
* 删除图书
* @param id
* @return
*/
@requestmapping(value="/delete",method = requestmethod.get)
public string delete(integer id) {
bookdao.delete(id);
return "forward:/book/list";
}
}
|
实现了 crud
这里的@getmapping(value="xxx") 类似 @requestmapping(value="xxx",method=requestmethod.get)
以及@postmapping(value="xxx") 类似 @requestmapping(value="xxx",method=requestmethod.post)
booklist.ftl 展示数据
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
|
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>图书管理页面</title>
</head>
<body>
<a href="/bookadd.html" rel="external nofollow" >添加图书</a>
<table>
<tr>
<th>编号</th>
<th>图书名称</th>
<th>操作</th>
</tr>
<#list booklist as book>
<tr>
<td>${book.id}</td>
<td>${book.bookname}</td>
<td>
<a href="/book/preupdate/${book.id}" rel="external nofollow" >修改</a>
<a href="/book/delete?id=${book.id}" rel="external nofollow" >删除</a>
</td>
</tr>
</#list>
</table>
</body>
</html>
|
bookadd.html 图书添加页面
|
1
2
3
4
5
6
7
8
9
10
11
12
13
|
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>图书添加页面</title>
</head>
<body>
<form action="book/add" method="post">
图书名称：<input type="text" name="bookname"/><br/>
<input type="submit" value="提交"/>
</form>
</body>
</html>
|
bookupdate.ftl图书修改页面
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
|
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>图书修改页面</title>
</head>
<body>
<form action="/book/update" method="post">
<input type="hidden" name="id" value="${book.id}"/>
图书名称：<input type="text" name="bookname" value="${book.bookname}"/><br/>
<input type="submit" value="提交"/>
</form>
</body>
</html>
|
浏览器请求：http://localhost:8888/book/list
进入：
点击 “添加图书”：
进入：
我们随便输入名称，点击“提交”，
选择刚才添加的测试图书，进行修改
转发执行到列表页面，然后点“修改”，
进入修改页面，修改下名称，点击“提交”，
选择测试图书，进行删除操作
再次转发到列表页面，我们点击“删除”，
删掉数据后，再次转发到列表页面；
ok完成！
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。
原文链接：https://www.cnblogs.com/jedjia/p/CRUD.html