JPA 查询All示例
JPA教程 - JPA查询All示例
我们可以在JPQL中使用带有子查询的ALL运算符。
List l = em.createQuery(
"SELECT e FROM Professor e WHERE e.salary < "
+ "ALL (SELECT d.salary FROM e.directs d)")
.getResultList();
例子
下面的代码来自PersonDaoImpl.java。
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 < "
+ "ALL (SELECT d.salary FROM e.directs d)")
.getResultList();
for (Object p : l) {
printResult(p);
}
}
private void prepareData() {
Professor p = new Professor();
p.setId(0);
p.setName("TOM");
p.setSalary(1111L);
Department d = new Department();
d.setId(1);
d.setName("Design");
p.setDepartment(d);
d.getProfessors().add(p);
em.persist(p);
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;
}
下面的代码来自Department.java。
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();
}
}
以下代码来自Professor.java。
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());
}
}
以下代码来自Project.java。
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Address.java。
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();
}
}
以下代码来自Phone.java。
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();
}
}
以下是数据库转储。
Table Name: ADDRESS
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
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: null
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
JPA 查询ANY示例
JPA教程 - JPA查询ANY示例
以下代码显示了如何在JPQL中使用ANY运算符。
List l = em.createQuery(
"SELECT e FROM Professor e WHERE e.department = ANY (SELECT DISTINCT d FROM Department d)")
.getResultList();
例子
下面的代码来自PersonDaoImpl.java。
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.department = ANY (SELECT DISTINCT d FROM Department d)")
.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Address.java。
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();
}
}
以下代码来自Professor.java。
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());
}
}
以下代码来自Phone.java。
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Department.java。
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();
}
}
以下代码来自Project.java。
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();
}
}
上面的代码生成以下结果。
以下是数据库转储。
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
JPA 查询IN示例
JPA教程 - JPA查询IN示例
IN表达式可以检查单值路径表达式是否是集合的成员。
集合可以内联定义为一组字面值,或者可以从子查询派生。
以下代码显示了如何在JPQL中使用IN运算符。
List l = em.createQuery(
"SELECT DISTINCT p FROM Professor e, IN(e.phones) p")
.getResultList();
以下代码显示如何使用NOT IN运算符
List l = em.createQuery(
"SELECT e FROM Professor e WHERE e.address.state NOT IN ("NY", "CA")")
.getResultList();
例子
下面的代码来自PersonDaoImpl.java。
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 DISTINCT p FROM Professor e, IN(e.phones) p")
.getResultList();
for (Object p : l) {
printResult(p);
}
}
private void prepareData() {
Professor p = new Professor();
p.setId(0);
p.setName("TOM");
p.setSalary(1111L);
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(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Address.java。
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();
}
}
以下代码来自Phone.java。
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Department.java。
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();
}
}
以下代码来自Project.java。
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。
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());
}
}
下载 Query_IN.zip
下载 Query_NOT_IN.zip
上面的代码生成以下结果。
以下是数据库转储。
Table Name: ADDRESS
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: null
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
JPA 查询IN一对多示例
JPA教程 - JPA查询IN一对多示例
以下JPQL显示如何在一对多映射中使用IN运算符。
executeAndPrintQuery("SELECT DISTINCT p FROM Employee e, IN(e.directs) p");
例子
下面的代码来自Department.java。
package cn.w3cschool.common;
import java.util.ArrayList;
import java.util.Collection;
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 Collection<Employee> employees;
public Department() {
employees = new ArrayList<Employee>();
}
public void setId(int id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setEmployees(Collection<Employee> employees) {
this.employees = employees;
}
public int getId() {
return id;
}
public String getName() {
return name;
}
public Collection<Employee> getEmployees() {
return employees;
}
public String toString() {
return "Department no: " + getId() +
", name: " + getName();
}
}
以下代码来自Project.java。
package cn.w3cschool.common;
import java.util.ArrayList;
import java.util.Collection;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
@Entity
public class Project {
@Id
protected int id;
protected String name;
@ManyToMany(mappedBy="projects")
private Collection<Employee> employees;
public Project() {
employees = new ArrayList<Employee>();
}
public void setId(int id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setEmployees(Collection<Employee> employees) {
this.employees = employees;
}
public int getId() {
return id;
}
public String getName() {
return name;
}
public Collection<Employee> getEmployees() {
return employees;
}
public String toString() {
return "Project id: " + getId() + ", name: " + getName();
}
}
以下代码来自Employee.java。
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.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
@Entity
public class Employee {
@Id
private int id;
private String name;
private long salary;
@Temporal(TemporalType.DATE)
private Date startDate;
@ManyToOne
private Employee manager;
@OneToMany(mappedBy="manager")
private Collection<Employee> directs;
@ManyToOne
private Department department;
@ManyToMany
private Collection<Project> projects;
public Employee() {
projects = new ArrayList<Project>();
directs = new ArrayList<Employee>();
}
public void setId(int id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setSalary(long salary) {
this.salary = salary;
}
public void setStartDate(Date startDate) {
this.startDate = startDate;
}
public void setManager(Employee manager) {
this.manager = manager;
}
public void setDirects(Collection<Employee> directs) {
this.directs = directs;
}
public void setDepartment(Department department) {
this.department = department;
}
public void setProjects(Collection<Project> projects) {
this.projects = projects;
}
public int getId() {
return id;
}
public String getName() {
return name;
}
public long getSalary() {
return salary;
}
public Date getStartDate() {
return startDate;
}
public Department getDepartment() {
return department;
}
public Collection<Employee> getDirects() {
return directs;
}
public Employee getManager() {
return manager;
}
public Collection<Project> getProjects() {
return projects;
}
public String toString() {
return "Employee " + getId() +
": name: " + getName() +
", salary: " + getSalary() +
", dept: " + ((getDepartment() == null) ? null : getDepartment().getName());
}
}
下面的代码来自PersonDaoImpl.java。
package cn.w3cschool.common;
import java.util.Arrays;
import java.util.Date;
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import org.springframework.transaction.annotation.Transactional;
@Transactional
public class PersonDaoImpl {
public void test() {
Employee emp = new Employee();
emp.setName("Tom");
emp.setSalary(123);
emp.setStartDate(new Date());
emp.setId(1);
Project pro = new Project();
pro.setName("Design");
pro.getEmployees().add(emp);
Department dept = new Department();
dept.setName("Dept");
dept.getEmployees().add(emp);
emp.setDepartment(dept);
emp.getProjects().add(pro);
em.persist(dept);
em.persist(pro);
em.persist(emp);
executeAndPrintQuery("SELECT DISTINCT p FROM Employee e, IN(e.directs) p");
}
private void executeAndPrintQuery(String queryString) {
try {
Query query = em.createQuery(queryString);
printQueryResult(queryString, query.getResultList());
} finally {
em.close();
}
}
private void printQueryResult(String queryString, List result) {
System.out.println("EJB QL: " + queryString+"\n");
System.out.println("Result:\n");
if (result.isEmpty()) {
System.out.println("No results Found\n");
} else {
for (Object o : result) {
System.out.println(resultAsString(o));
}
}
}
private String resultAsString(Object o) {
if (o instanceof Object[]) {
return Arrays.asList((Object[])o).toString();
} else {
return String.valueOf(o);
}
}
@PersistenceContext
private EntityManager em;
}
上面的代码生成以下结果。
以下是数据库转储。
Table Name: DEPARTMENT
Row:
Column Name: ID,
Column Type: INTEGER:
Column Value: 0
Column Name: NAME,
Column Type: VARCHAR:
Column Value: Dept
Table Name: EMPLOYEE
Row:
Column Name: ID,
Column Type: INTEGER:
Column Value: 1
Column Name: NAME,
Column Type: VARCHAR:
Column Value: Tom
Column Name: SALARY,
Column Type: BIGINT:
Column Value: 123
Column Name: STARTDATE,
Column Type: DATE:
Column Value: 2014-12-29
Column Name: DEPARTMENT_ID,
Column Type: INTEGER:
Column Value: 0
Column Name: MANAGER_ID,
Column Type: INTEGER:
Column Value: null
Table Name: EMPLOYEE_PROJECT
Row:
Column Name: EMPLOYEES_ID,
Column Type: INTEGER:
Column Value: 1
Column Name: PROJECTS_ID,
Column Type: INTEGER:
Column Value: 0
Table Name: PROJECT
Row:
Column Name: ID,
Column Type: INTEGER:
Column Value: 0
Column Name: NAME,
Column Type: VARCHAR:
Column Value: Design