智能商贸系统day1

智能商贸系统day1（Spring+SpringMVC+SpringDataJPA）

一：项目搭建

1.使用ideal搭建项目—maven项目选择webapp
2. 完整结构为

3. 导入项目需要的jar依赖

    UTF-8
    1.8
    1.8
    4.2.5.RELEASE
    4.3.8.Final
    1.9.0.RELEASE
    2.5.0
    1.6.3
  



 
    
    
      org.springframework
      spring-core
      ${org.springframework.version}
    
    
      org.springframework
      spring-context
      ${org.springframework.version}
    

  org.springframework
  spring-context-support
  ${org.springframework.version}


事务需要

  org.springframework
  spring-tx
  ${org.springframework.version}


  org.springframework
  spring-jdbc
  ${org.springframework.version}



  org.springframework
  spring-orm
  ${org.springframework.version}


  org.springframework
  spring-aop
  ${org.springframework.version}


  org.springframework
  spring-test
  ${org.springframework.version}
  test



  org.springframework
  spring-web
  ${org.springframework.version}


  org.springframework
  spring-webmvc
  4.2.4.RELEASE



  org.apache.commons
  commons-io
  1.3.2



  commons-fileupload
  commons-fileupload
  1.2.2



  com.fasterxml.jackson.core
  jackson-core
  ${com.fasterxml.jackson.version}


  com.fasterxml.jackson.core
  jackson-annotations
  ${com.fasterxml.jackson.version}


  com.fasterxml.jackson.core
  jackson-databind
  ${com.fasterxml.jackson.version}



  org.hibernate
  hibernate-core
  ${org.hibernate.version}


  org.hibernate
  hibernate-entitymanager
  ${org.hibernate.version}




  org.springframework.data
  spring-data-jpa
  ${spring-data-jpa.version}




  com.github.wenhao
  jpa-spec
  3.1.1
  
  
    
      *
      *
    
  



  commons-dbcp
  commons-dbcp
  1.2.2



  mysql
  mysql-connector-java
  5.1.6


 

  org.apache.commons
  commons-lang3
  3.5




  junit
  junit
  4.12
  test


  javax.servlet
  javax.servlet-api
  3.1.0
  
  provided



  org.slf4j
  slf4j-api
  ${org.slf4j.version}


  org.slf4j
  slf4j-log4j12
  ${org.slf4j.version}
  runtime


  log4j
  log4j
  1.2.14



  org.apache.velocity
  velocity
  1.6



  org.apache.shiro
  shiro-all
  1.4.0
  pom



  org.apache.shiro
  shiro-spring
  1.4.0



  org.apache.poi
  poi
  3.11


  org.apache.poi
  poi-ooxml
  3.11




  net.coobird
  thumbnailator
  0.4.6



  quartz
  quartz
  1.5.2



  javax.mail
  mail
  1.4.1

`
4 创建applicationContext.xml配置文件配置如下

5 建立程序结构

6 完成实体类—由于主键id很多类都需要，抽取一个父类专门实现主键id

import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.MappedSuperclass;
/*
	使用@MappedSuperclass注解，通过这个注解，我们可以将该实体类当成基类实体
	在这里插入代码片，它不会映射到数据库表，
	但继承它的子类实体在映射时会自动扫描该基类实体的映射属性，
	添加到子类实体的对应数据库表中。
*/
@MappedSuperclass
public class BaseDomain {
    @Id
    @GeneratedValue
    protected  Long id;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }
}

7 Employee实体类类实现

import javax.persistence.Entity;
import javax.persistence.Table;

@Entity
@Table(name = "employee")
public class Employee extends BaseDomain {
	//雇员姓名
    private String username;
    //雇员密码
    private String password;
    //雇员邮件
    private String email;
    //员工年龄
    private Integer age;
    @Override
    public String toString() {
        return "Employee{" +
                "username='" + username + '\'' +
                ", password='" + password + '\'' +
                ", email='" + email + '\'' +
                ", age=" + age +
                ", id=" + id +
                '}';
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }
}

8 Repository(也就是Dao)层实现----SpringDataJPA进一步封装JPA，只需写一个接口继承一个接口即可完成crud操作。

public interface EmployeeRepository extends JpaRepository{
}

9 通过8可以完成一些简单的crud即分页排序与高级查询（通过根据规则写查询方法或者使用@Query注解）
规则如下:

public interface EmployeeRepository extends JpaRepository, JpaSpecificationExecutor {
    //通过定义的规则提供简单查询
    List findByUsernameLike(String username);
    //使用query注解使用jpql或者sql语句查询
    //@Query("select o from Employee o where o.username like ?1")
    @Query(value = "select * from employee where username like ?",nativeQuery = true)
    List findUsername(String name);
    List findByUsernameLikeAndEmailLike(String username,String email);
}

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class TestEmployee {
    @Autowired
    private EmployeeRepository employeeRepository;

    /*查询数据*/
    @Test
    public void testFind() throws Exception{
        List list = employeeRepository.findAll();
        list.forEach(e -> System.out.println(e));
    }
    //添加数据
    @Test
    public void testAdd() throws Exception{
        Employee employee = new Employee();
        employee.setUsername("张三");
        employee.setAge(12);
        employee.setEmail("[email protected]");
        employeeRepository.save(employee);
    }
    //修改数据
    @Test
    public void testUpdate() throws Exception{
        Employee employee = new Employee();
        employee.setUsername("张三");
        employee.setAge(12);
        employee.setId(274L);
        employee.setEmail("[email protected]");
        employeeRepository.save(employee);
    }
    //删除数据
    @Test
    public void testDelete() throws Exception{
        employeeRepository.delete(274L);
    }
    //分页
    @Test
    public void testPage() throws Exception{
        /*当前页从0开始*/
        Pageable pageable=new PageRequest(0, 10);
        Page list = employeeRepository.findAll(pageable);
        list.forEach(e-> System.out.println(e));
    }
    //排序
    @Test
    public void testOrder() throws Exception{
        Sort sort=new Sort(Sort.Direction.ASC,"username");
        List li = employeeRepository.findAll(sort);
        li.forEach(e-> System.out.println(e));
    }

10 但是一些高级查询还是要写查询语句----这里继承JpaSpecificationExecutor接口可以不用写jpql便能完成高级查询，使用方法如下

//查询+排序+分页
    @Test
    public void testQuery3() throws Exception{
        Sort sort=new Sort(Sort.Direction.ASC, "username");
        Pageable pageable=new PageRequest(0, 10,sort);
        Page username = employeeRepository.findAll(new Specification() {
            /*
             * root相当于类或者表
             * cb相当于查询条件
             * */
            @Override
            public Predicate toPredicate(Root root, CriteriaQuery query, CriteriaBuilder cb) {
                //拿到要查询的字段
                Path path = root.get("username");
                //设置查询的值
                Predicate like = cb.like(path, "%1%");
                return like;
            }
        },pageable/*sort*/);
        username.forEach(e-> System.out.println(e));
    }

11 发现代码还是有点多—这里用了文浩大佬集成的一个jpa-specbao
导入依赖

    
      com.github.wenhao
      jpa-spec
      3.1.1
      
      
        
          *
          *
        
      
    

发现代码变得简单多了（具体使用请进入https://github.com/wenhao/jpa-spec查看）

 //jpa-spec 分页+排序+查询
    @Test
    public void testQuery4() throws Exception{
        Sort sort=new Sort(Sort.Direction.ASC, "username");
        Pageable pageable=new PageRequest(0, 10,sort);
        Specification username = Specifications.and()
                .like("username","%1%")
                .build();
        Page list = employeeRepository.findAll(username,pageable);
        list.forEach(e-> System.out.println(e));
    }

12 这里我们发现如果前台传入查询条件我们就必须要写一个类去接收

父类实现一些公共的查询条件（比如当前页，每页分页条数，排序类型–升序/降序，排序字段）

import org.apache.commons.lang3.StringUtils;
import org.springframework.data.domain.Sort;
import org.springframework.data.jpa.domain.Specification;

/*提供公共的查询条件
* 规范
* */
public abstract class BaseQuery {
    /*一些公共的查询条件*/
    //当前页
    private int currentPage=1;
    //当前页数量
    private int pageSize=5;
    //排序名称
    private String OrderByname;
    //排序类型
    private String OrderByType= "ASC";

    //获得从0开始的分页
    public int getJpaCurrentPage(){
        return this.currentPage-1;
    }

    /*规定子类必须实现这个方法,用来获得Specification对象*/
    protected abstract Specification getSpec();
    /*获得排序*/
    public Sort getSort(){
        Sort sort=null;
        Sort.Direction desc = Sort.Direction.DESC;
        if(StringUtils.isNoneBlank(OrderByname)){
            if("ASC".equals(OrderByType.toUpperCase())){
                //如果用户传入的是ASC
                desc=Sort.Direction.ASC;
            }
            sort=new Sort(desc,OrderByname);
        }
        return sort;
    }
    public int getCurrentPage() {
        return currentPage;
    }

    public void setCurrentPage(int curentPage) {
        this.currentPage = curentPage;
    }

    public int getPageSize() {
        return pageSize;
    }

    public void setPageSize(int pageSize) {
        this.pageSize = pageSize;
    }

    public String getOrderByname() {
        return OrderByname;
    }

    public void setOrderByname(String orderByname) {
        OrderByname = orderByname;
    }

    public String getOrderByType() {
        return OrderByType;
    }

    public void setOrderByType(String orderByType) {
        OrderByType = orderByType;
    }
}

import cn.itsource.aisale.domain.Employee;
import com.github.wenhao.jpa.Specifications;
import org.apache.commons.lang3.StringUtils;
import org.springframework.data.jpa.domain.Specification;

public class EmployeeQuery extends BaseQuery {
    /*写自己独有的查询条件*/
    private String username;
    private String email;
    private Integer age;

    public String getUsername() {
        return username;
    }

    //获得Specifications
    public Specification getSpec(){
        Specification spec = Specifications.and()
                /*问题：
                 * 因为无法判断用户是否传入条件，需要判断条件是否为空
                 * */
                .like(StringUtils.isNoneBlank(username),"username",username)
                .like(StringUtils.isNoneBlank(email),"email", email)
                .lt(age!=null,"age",age)
                .build();
        return spec;
    }
    public void setUsername(String username) {
        this.username = username;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }
}