springboot对jpa的支持以及与bootstrap的简单增删查改+图片上传
一、jpa是什么
JPA全称Java Persistence API，是一组用于将数据存入数据库的类和方法的集合。JPA通过JDK 5.0注解或XML描述对象－关系表的映射关系，并将运行期的实体对象持久化到数据库中。 简单说jpa是jdk对数据库提供的接口，可以自动生成表。
二、springboot对jpa的配置
1、创建springboot项目时勾选jpa配置
2、在pom.xml添加依赖
org.springframework.boot
spring-boot-starter-data-jpa
3、application.yml配置
spring:
jpa:
hibernate:
ddl-auto: update
show-sql: true4、创建一个实体类
注解：
@Entity
@Table(name="表名"）
@Id
@GeneratedValue//主键
@Column(length = 100)//列
import javax.persistence.*;
/**
* @author 疯子侠
* @site www.donggua.com
* @company donggua公司
* @create 2019-02-22 21:27
*/
@Entity
@Table(name = "t_springboot_person")
public class Person {
@Id
@GeneratedValue
private Integer tid;
@Column(length = 100)
private String Pdesc;
@Column(length = 300)
private String image_path;
@Column(length = 10)
private String sex;
@Column(length = 100)
private String name;
public Integer getTid() {
return tid;
}
public void setTid(Integer tid) {
this.tid = tid;
}
public String getPdesc() {
return Pdesc;
}
public void setPdesc(String pdesc) {
Pdesc = pdesc;
}
public String getImage_path() {
return image_path;
}
public void setImage_path(String image_path) {
this.image_path = image_path;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
启动类在数据库就会生成一张表和一个序列表
5、继承JpaRepository<实体类,主键的id类型>, JpaSpecificationExecutor<实体类>就有了增删查改的方法
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
public interface PersonDao extends JpaRepository , JpaSpecificationExecutor {
}
实现类
serviceImpl层:
@Service
public class PersonServiceImpl implements PersonService {
@Autowired
private PersonDao personDao;
@Override
public Person save(Person person) {
//在jpa中，增加和修改都是同一个方法
return personDao.save(person);
}
@Override
public void deleteById(Integer tid) {//删除
personDao.deleteById(tid);
}
@Override
public Person findById(Integer tid) {//查单个
//查单个的方法是findById().get(),若用.getOne()这个方法会报错
return personDao.findById(tid).get();
}
@Override
public Page listPager(Person person, PageBean pageBean) {
//jpa的Pageable分页是从0页码开始
//PageBean.start('当前页'，‘当也展示记录数’)
Pageable pageable = PageRequest.of(pageBean.getPage()-1, pageBean.getRows());
return personDao.findAll(new Specification() {
@Override
public Predicate toPredicate(Root root, CriteriaQuery criteriaQuery, CriteriaBuilder criteriaBuilder) {
Predicate predicate = criteriaBuilder.conjunction();
if(person != null){
if(Stringutil.isNotBlank(person.getName())){
predicate.getExpressions().add(criteriaBuilder.like(root.get("name"),"%"+person.getName()+"%"));
}
}
return predicate;
}
},pageable);
}
}
service层 ：
public Person save(Person person) ;
public void deleteById(Integer tid);
public Person findById(Integer tid) ;
public Page listPager(Person person, PageBean pageBean); 三、springboot+jpa+bootstrap做一个简单的增删查改以及图片上传
pom.xml要添加图片上传的依赖
commons-fileupload
commons-fileupload
1.3.1
application.yml配置添加配置
# 解决图片上传大小限制问题，也可采取配置类
servlet:
multipart:
max-file-size: 20MB
max-request-size: 60MBconfig
springboot内嵌tomcat用配置关联
@Configuration
public class MyWebAppConfigurer extends WebMvcConfigurationSupport {
@Override
protected void addResourceHandlers(ResourceHandlerRegistry registry) {
registry.addResourceHandler("/static/**").addResourceLocations("classpath:/static/");
registry.addResourceHandler("/images/**").addResourceLocations("file:E:/temp/");
super.addResourceHandlers(registry);
}
}
controller层
@Controller
@RequestMapping("/person")
public class PersonController {
@Autowired
private PersonService personService;
@RequestMapping("/listPager")
public ModelAndView list(Person person, HttpServletRequest request){
PageBean pageBean = new PageBean();
pageBean.setRequest(request);
ModelAndView modelAndView = new ModelAndView();
Page persons = personService.listPager(person, pageBean);
modelAndView.addObject("persons",persons.getContent());
pageBean.setTotal(persons.getTotalElements()+"");
modelAndView.addObject("pageCode", PageUtil.createPageCode(pageBean)/*.replaceAll("<","<").replaceAll(">:",">")*/);
modelAndView.setViewName("list");
return modelAndView;
}
@RequestMapping("/toEdit")
public ModelAndView toEdit(Person person){
ModelAndView modelAndView = new ModelAndView();
modelAndView.setViewName("edit");
modelAndView.addObject("sexArr",new String[]{"男","女"});
if(!(person.getTid() == null || "".equals(person.getTid()))) {
Person t = personService.findById(person.getTid());
modelAndView.addObject("person", t);
}
return modelAndView;
}
@RequestMapping("/add")
public String add(Person person, MultipartFile image){
try {
String diskPath = "E://temp/"+image.getOriginalFilename();
String serverPath = "http://localhost:8080/springboot/images/"+image.getOriginalFilename();
if(Stringutil.isNotBlank(image.getOriginalFilename())){
FileUtils.copyInputStreamToFile(image.getInputStream(),new File(diskPath));
person.setImage_path(serverPath);
}
personService.save(person);
} catch (IOException e) {
e.printStackTrace();
}
return "redirect:/person/listPager";
}
@RequestMapping("/edit")
public String edit(Person person, MultipartFile image){
String diskPath = "E://temp/"+image.getOriginalFilename();
String serverPath = "http://localhost:8080/springboot/images/"+image.getOriginalFilename();
if(Stringutil.isNotBlank(image.getOriginalFilename())){
try {
FileUtils.copyInputStreamToFile(image.getInputStream(),new File(diskPath));
person.setImage_path(serverPath);
} catch (IOException e) {
e.printStackTrace();
}
}
personService.save(person);
return "redirect:/person/listPager";
}
@RequestMapping("/del/{bid}")
public String del(@PathVariable(value = "bid") Integer bid){
personService.deleteById(bid);
return "redirect:/person/listPager";
}
} pageBean
public class PageBean {
private int page = 1;// 页码
private int rows = 3;// 页大小
private int total = 0;// 总记录数
private boolean pagination = true;// 是否分页
// 保存上次查询的参数
private Map paramMap;
// 保存上次查询的url
private String url;
public void setRequest(HttpServletRequest request) {
String page = request.getParameter("page");
String rows = request.getParameter("offset");
String pagination = request.getParameter("pagination");
this.setPage(page);
this.setRows(rows);
this.setPagination(pagination);
this.setUrl(request.getRequestURL().toString());
this.setParamMap(request.getParameterMap());
}
public PageBean() {
super();
}
public Map getParamMap() {
return paramMap;
}
public void setParamMap(Map paramMap) {
this.paramMap = paramMap;
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public int getPage() {
return page;
}
public void setPage(int page) {
this.page = page;
}
public void setPage(String page) {
if(Stringutil.isNotBlank(page)) {
this.page = Integer.parseInt(page);
}
}
public int getRows() {
return rows;
}
public void setRows(String rows) {
if(Stringutil.isNotBlank(rows)) {
this.rows = Integer.parseInt(rows);
}
}
public int getTotal() {
return total;
}
public void setTotal(int total) {
this.total = total;
}
public void setTotal(String total) {
if(Stringutil.isNotBlank(total)) {
this.total = Integer.parseInt(total);
}
}
public boolean isPagination() {
return pagination;
}
public void setPagination(boolean pagination) {
this.pagination = pagination;
}
public void setPagination(String pagination) {
if(Stringutil.isNotBlank(pagination) && "false".equals(pagination)) {
this.pagination = Boolean.parseBoolean(pagination);
}
}
/**
* 最大页
* @return
*/
public int getMaxPage() {
int max = this.total/this.rows;
if(this.total % this.rows !=0) {
max ++ ;
}
return max;
}
/**
* 下一页
* @return
*/
public int getNextPage() {
int nextPage = this.page + 1;
if(nextPage > this.getMaxPage()) {
nextPage = this.getMaxPage();
}
return nextPage;
}
/**
* 上一页
* @return
*/
public int getPreviousPage() {
int previousPage = this.page -1;
if(previousPage < 1) {
previousPage = 1;
}
return previousPage;
}
/**
* 获得起始记录的下标
*
* @return
*/
public int getStartIndex() {
return (this.page - 1) * this.rows;
}
@Override
public String toString() {
return "PageBean [page=" + page + ", rows=" + rows + ", total=" + total + ", pagination=" + pagination + "]";
}
} Stingutil
public class Stringutil {
// 私有的构造方法，保护此类不能在外部实例化
private Stringutil() {
}
/**
* 如果字符串等于null或去空格后等于""，则返回true，否则返回false
*
* @param s
* @return
*/
public static boolean isBlank(String s) {
boolean b = false;
if (null == s || s.trim().equals("")) {
b = true;
}
return b;
}
/**
* 如果字符串不等于null或去空格后不等于""，则返回true，否则返回false
*
* @param s
* @return
*/
public static boolean isNotBlank(String s) {
return !isBlank(s);
}
}
PageUtil
public class PageUtil {
public static String createPageCode(PageBean pageBean) {
StringBuffer sb = new StringBuffer();
/*
* 拼接向后台提交数据的form表单
* 注意：拼接的form表单中的page参数是变化的，所以不需要保留上一次请求的值
*/
sb.append("");
if(pageBean.getTotal()==0){
return "未查询到数据";
}else{
sb.append("首页 ");
if(pageBean.getPage()>1){
sb.append("上一页 ");
}else{
sb.append("上一页 ");
}
for(int i=pageBean.getPage()-1;i<=pageBean.getPage()+1;i++){
if(i<1||i>pageBean.getMaxPage()){
continue;
}
if(i==pageBean.getPage()){
sb.append(""+i+" ");
}else{
sb.append(""+i+" ");
}
}
if(pageBean.getPage()下一页");
}else{
sb.append("下一页 ");
}
sb.append("尾页 ");
}
/*
* 给分页条添加与后台交互的js代码
*/
sb.append("");
return sb.toString();
}
} 前端代码
list.html
Title
新增
ID
头像
姓名
性别
简介
操作
![]()
删除
修改
edit.html
用户编辑界面
运行后的效果
