第二百六十七节 JPA教程 - JPA查询AND条件示例

程序猿小D2024-10-06 9:33

JPA教程 - JPA查询AND条件示例

以下JPQL显示如何使用AND组合两个条件。

复制代码 
"SELECT e FROM Professor e WHERE e.salary >= 40 AND e.salary <= 50")

例子

以下代码来自Address.java。

复制代码 
package cn.w3cschool.common;

import javax.persistence.Entity;
import javax.persistence.Id;

@Entity
public class Address {
    @Id
    private int id;
    private String street;
    private String city;
    private String state;
    private String zip;
    
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    
    public String getStreet() {
        return street;
    }
    
    public void setStreet(String address) {
        this.street = address;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

    public String getState() {
        return state;
    }

    public void setState(String state) {
        this.state = state;
    }

    public String getZip() {
        return zip;
    }

    public void setZip(String zip) {
        this.zip = zip;
    }
    public String toString() {
        return "Address id: " + getId() + 
               ", street: " + getStreet() +
               ", city: " + getCity() +
               ", state: " + getState() +
               ", zip: " + getZip();
    }

}

下面的代码来自Department.java。

复制代码 
package cn.w3cschool.common;

import java.util.HashSet;
import java.util.Set;

import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToMany;

@Entity
public class Department {
    @Id
    private int id;
    private String name;
    @OneToMany(mappedBy="department")
    private Set<Professor> employees = new HashSet<Professor>();

    public int getId() {
        return id;
    }
    
    public void setId(int deptNo) {
        this.id = deptNo;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String deptName) {
        this.name = deptName;
    }
    
    public Set<Professor> getProfessors() {
        return employees;
    }

    public String toString() {
        return "Department no: " + getId() + 
               ", name: " + getName();
    }
}

下面的代码来自PersonDaoImpl.java。

复制代码 
package cn.w3cschool.common;

import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

import org.springframework.transaction.annotation.Transactional;

@Transactional
public class PersonDaoImpl {
  public void test() {
    prepareData();
    
    List l = em.createQuery(
        "SELECT e FROM Professor e WHERE e.salary >= 40 AND e.salary <= 50")
        .getResultList();
    for (Object p : l) {
      printResult(p);
    }
  }

  private void prepareData() {
    Address address = new Address();
    address.setState("BC");
    
    Professor p = new Professor();
    p.setId(0);
    p.setName("TOM");
    p.setSalary(1111L);
    p.setAddress(address);

    Department d = new Department();
    d.setId(1);
    d.setName("Design");

    p.setDepartment(d);
    d.getProfessors().add(p);

    Phone phone = new Phone();
    phone.setId(1);
    phone.setNumber("111-111-1111");
    phone.setProfessor(p);
    
    em.persist(p);
    em.persist(phone);
    em.persist(address);
    em.persist(d);
  }

  private static void printResult(Object result) {
    if (result == null) {
      System.out.print("NULL");
    } else if (result instanceof Object[]) {
      Object[] row = (Object[]) result;
      System.out.print("[");
      for (int i = 0; i < row.length; i++) {
        printResult(row[i]);
      }
      System.out.print("]");
    } else if (result instanceof Long || result instanceof Double
        || result instanceof String) {
      System.out.print(result.getClass().getName() + ": " + result);
    } else {
      System.out.print(result);
    }
    System.out.println();
  }

  @PersistenceContext
  private EntityManager em;
}

以下代码来自Phone.java。

复制代码 
package cn.w3cschool.common;

import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToOne;

@Entity
public class Phone {
    @Id
    private long id;
    private String number;
    private String type;
    @ManyToOne
    Professor employee;
    
    public long getId() {
        return id;
    }
    
    public void setId(long id) {
        this.id = id;
    }
    
    public String getNumber() {
        return number;
    }
    
    public void setNumber(String phoneNo) {
        this.number = phoneNo;
    }
    
    public String getType() {
        return type;
    }
    
    public void setType(String phoneType) {
        this.type = phoneType;
    }
    
    public Professor getProfessor() {
        return employee;
    }

    public void setProfessor(Professor employee) {
        this.employee = employee;
    }

    public String toString() {
        return "Phone id: " + getId() + 
               ", no: " + getNumber() +
               ", type: " + getType();
    }
}

下面的代码来自Helper.java。

复制代码 
package cn.w3cschool.common;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;

public class Helper {
  public static void checkData()  {
    try{
      Class.forName("org.hsqldb.jdbcDriver");
      Connection conn = DriverManager.getConnection("jdbc:hsqldb:mem:mydatabase", "sa", "");
      Statement st = conn.createStatement();

      ResultSet mrs = conn.getMetaData().getTables(null, null, null, new String[] { "TABLE" });
      while (mrs.next()) {
        String tableName = mrs.getString(3);
        System.out.println("\n\n\n\nTable Name: "+ tableName);

        ResultSet rs = st.executeQuery("select * from " + tableName);
        ResultSetMetaData metadata = rs.getMetaData();
        while (rs.next()) {
          System.out.println(" Row:");
          for (int i = 0; i < metadata.getColumnCount(); i++) {
            System.out.println("    Column Name: "+ metadata.getColumnLabel(i + 1)+ ",  ");
            System.out.println("    Column Type: "+ metadata.getColumnTypeName(i + 1)+ ":  ");
            Object value = rs.getObject(i + 1);
            System.out.println("    Column Value: "+value+"\n");
          }
        }
      }
    }catch(Exception e){
      e.printStackTrace();
    }
 }
}

以下代码来自Project.java。

复制代码 
package cn.w3cschool.common;

import java.util.ArrayList;
import java.util.Collection;

import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.ManyToMany;

@Entity
@Inheritance
public class Project {
    @Id
    protected int id;
    protected String name;
    @ManyToMany
    protected Collection<Professor> employees = new ArrayList<Professor>();
    
    public int getId() {
        return id;
    }
    
    public void setId(int projectNo) {
        this.id = projectNo;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String projectName) {
        this.name = projectName;
    }
    
    public Collection<Professor> getProfessors() {
        return employees;
    }
    
    public void addProfessor(Professor employee) {
        if (!getProfessors().contains(employee)) {
            getProfessors().add(employee);
        }
        if (!employee.getProjects().contains(this)) {
            employee.getProjects().add(this);
        }
    }
    
    public String toString() {
        return getClass().getName().substring(getClass().getName().lastIndexOf(".")+1) + 
                " no: " + getId() + 
                ", name: " + getName();
    }
}

以下代码来自Professor.java。

复制代码 
package cn.w3cschool.common;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;

import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;

@Entity
public class Professor {
    @Id
    private int id;
    private String name;
    private long salary;
    @Temporal(TemporalType.DATE)
    private Date startDate;
    
    @OneToOne
    private Address address;
    
    @OneToMany(mappedBy="employee")
    private Collection<Phone> phones = new ArrayList<Phone>();
    
    @ManyToOne
    private Department department;
    
    @ManyToOne
    private Professor manager;
    
    @OneToMany(mappedBy="manager")
    private Collection<Professor> directs = new ArrayList<Professor>();
    
    @ManyToMany(mappedBy="employees")
    private Collection<Project> projects = new ArrayList<Project>();

    public int getId() {
        return id;
    }
    
    public void setId(int empNo) {
        this.id = empNo;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String name) {
        this.name = name;
    }

    public long getSalary() {
        return salary;
    }

    public void setSalary(long salary) {
        this.salary = salary;
    }

    public Date getStartDate() {
        return startDate;
    }

    public void setStartDate(Date startDate) {
        this.startDate = startDate;
    }
    
    public Collection<Phone> getPhones() {
        return phones;
    }
    
    public void addPhone(Phone phone) {
        if (!getPhones().contains(phone)) {
            getPhones().add(phone);
            if (phone.getProfessor() != null) {
                phone.getProfessor().getPhones().remove(phone);
            }
            phone.setProfessor(this);
        }
    }
    
    public Department getDepartment() {
        return department;
    }
    
    public void setDepartment(Department department) {
        if (this.department != null) {
            this.department.getProfessors().remove(this);
        }
        this.department = department;
        this.department.getProfessors().add(this);
    }
    
    public Collection<Professor> getDirects() {
        return directs;
    }
    
    public void addDirect(Professor employee) {
        if (!getDirects().contains(employee)) {
            getDirects().add(employee);
            if (employee.getManager() != null) {
                employee.getManager().getDirects().remove(employee);
            }
            employee.setManager(this);
        }
    }
    
    public Professor getManager() {
        return manager;
    }
    
    public void setManager(Professor manager) {
        this.manager = manager;
    }

    public Collection<Project> getProjects() {
        return projects;
    }
    
    public void addProject(Project project) {
        if (!getProjects().contains(project)) {
            getProjects().add(project);
        }
        if (!project.getProfessors().contains(this)) {
            project.getProfessors().add(this);
        }
    }
    
    public Address getAddress() {
        return address;
    }
    
    public void setAddress(Address address) {
        this.address = address; 
    }
    
    public String toString() {
        return "Professor " + getId() + 
               ": name: " + getName() +
               ", salary: " + getSalary() +
               ", phones: " + getPhones() +
               ", managerNo: " + ((getManager() == null) ? null : getManager().getId()) +
               ", deptNo: " + ((getDepartment() == null) ? null : getDepartment().getId());
    }

}

以下是数据库转储。

复制代码 
Table Name: ADDRESS
 Row:
    Column Name: ID,
    Column Type: INTEGER:
    Column Value: 0

    Column Name: CITY,
    Column Type: VARCHAR:
    Column Value: null

    Column Name: STATE,
    Column Type: VARCHAR:
    Column Value: BC

    Column Name: STREET,
    Column Type: VARCHAR:
    Column Value: null

    Column Name: ZIP,
    Column Type: VARCHAR:
    Column Value: null





Table Name: DEPARTMENT
 Row:
    Column Name: ID,
    Column Type: INTEGER:
    Column Value: 1

    Column Name: NAME,
    Column Type: VARCHAR:
    Column Value: Design





Table Name: PHONE
 Row:
    Column Name: ID,
    Column Type: BIGINT:
    Column Value: 1

    Column Name: NUMBER,
    Column Type: VARCHAR:
    Column Value: 111-111-1111

    Column Name: TYPE,
    Column Type: VARCHAR:
    Column Value: null

    Column Name: EMPLOYEE_ID,
    Column Type: INTEGER:
    Column Value: 0





Table Name: PROFESSOR
 Row:
    Column Name: ID,
    Column Type: INTEGER:
    Column Value: 0

    Column Name: NAME,
    Column Type: VARCHAR:
    Column Value: TOM

    Column Name: SALARY,
    Column Type: BIGINT:
    Column Value: 1111

    Column Name: STARTDATE,
    Column Type: DATE:
    Column Value: null

    Column Name: ADDRESS_ID,
    Column Type: INTEGER:
    Column Value: 0

    Column Name: DEPARTMENT_ID,
    Column Type: INTEGER:
    Column Value: 1

    Column Name: MANAGER_ID,
    Column Type: INTEGER:
    Column Value: null

Table Name: PROJECT




Table Name: PROJECT_PROFESSOR
相关推荐
程序猿阿伟2 分钟前
《探索 Apache Spark MLlib 与 Java 结合的卓越之道》
java·spark-ml·apache
一條狗7 分钟前
隨筆 20241224 ts寫入excel表
开发语言·前端·typescript
NY610 分钟前
mysql运维篇笔记——日志，主从复制，分库分表，读写分离
数据库·sql
向阳121811 分钟前
sentinel来源访问控制（黑白名单）
java·sentinel
Takumilove11 分钟前
MQTT入门：在Spring Boot中建立连接及测试
java·spring boot·后端
小码快撩12 分钟前
vue应用移动端访问缓慢问题
前端·javascript·vue.js
低调之人16 分钟前
Fiddler勾选https后google浏览器网页访问不可用
前端·测试工具·https·fiddler·hsts
yayaya15220 分钟前
javaScriptBOM
开发语言·javascript·ecmascript
Riesenzahn21 分钟前
使用vue如何监听元素尺寸的变化？
前端·javascript
潜洋24 分钟前
Spring Boot 教程之三十六：实现身份验证
java·数据库·spring boot
热门推荐
01SQL 主从数据库实时备份02YOLOv8训练好模型后，追加轮数继续训练、或者提前终止训练，缩减训练轮数03玄机平台应急响应—webshell查杀04VSCode插件 —— Cody AI （免费AI助手！）05HCIA-datacom数通题库和录播视频资料06Docker 夺命连环 15 问07组基轨迹建模 GBTM的介绍与实现（Stata 或 R）08校验 GPT-4 真实性的三个经典问题：快速区分 GPT-3.5 与 GPT-4，并提供免费测试网站09(欧拉)openEuler系统添加网卡文件配置流程、(欧拉)openEuler系统手动配置ipv6地址流程、(欧拉)openEuler系统网络管理说明10【华东南AWDP】第十七届全国大学生信息安全竞赛 CISCN 2024 创新实践能力赛区域赛 部分题解WP