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下面通过一个实际的列子来展示Hibernate的基本用法。

实例：

package com.ydoing.domain;import java.util.ArrayList;import java.util.Date;import java.util.HashMap;import java.util.HashSet;import java.util.List;import java.util.Map;import java.util.Set;import javax.persistence.Basic;import javax.persistence.CollectionTable;import javax.persistence.Column;import javax.persistence.ElementCollection;import javax.persistence.Entity;import javax.persistence.FetchType;import javax.persistence.GeneratedValue;import javax.persistence.GenerationType;import javax.persistence.Id;import javax.persistence.JoinColumn;import javax.persistence.Lob;import javax.persistence.MapKeyClass;import javax.persistence.MapKeyColumn;import javax.persistence.OrderColumn;import javax.persistence.Table;import javax.persistence.Temporal;import javax.persistence.TemporalType;import javax.persistence.Transient;import org.hibernate.annotations.Formula;@Entity@Table(name = "person")public class Person {
       // 主键为ＩＤ，最好设置为包装类型Integer    @Id    @Column(name = "person_id")    @GeneratedValue(strategy = GenerationType.AUTO)    private Integer id;    // 指定字符长度    @Column(name = "name", length = 50, nullable = false)    private String name;    @Column(name = "age")    private int age;    // 也可以不指定列名，默认为类的属性名    @Column    private String sex;    // @Transient表示不用持久化    @Transient    private String alias;    // @Lob表示大数据类型，FetchType.LAZY表示延迟加载，减少性能开销    @Lob    @Basic(fetch = FetchType.LAZY)    private byte[] image;    // 指定为日期类型    @Temporal(TemporalType.DATE)    private Date birthdate;    // 属性动态生成    @Formula("(select concat(p.name, p.age, p.sex) from person p where p.person_id = person_id)")    private String profile;    // List集合类型    // 需要显示初始化集合的类型    @ElementCollection(targetClass = String.class)    @CollectionTable(name = "pet_inf",// 指定表名    // 用于映射外键    joinColumns = @JoinColumn(name = "person_id", nullable = false))    @Column(name = "pet_name")    @OrderColumn(name = "list_order")    private List
   
     pets = new ArrayList<>();    // 数组属性    @ElementCollection(targetClass = String.class)    @CollectionTable(name = "school_inf", joinColumns = @JoinColumn(name = "person_id", nullable = false))    @Column(name = "school_name")    @OrderColumn(name = "array_order")    private String[] schools;    // Set集合属性,Set是无序的，不可重复的，因此Set集合属性无须使用@OrderColumn注解映射集合的索引列    @ElementCollection(targetClass = String.class)    @CollectionTable(name = "car_inf", joinColumns = @JoinColumn(name = "person_id", nullable = false))    @Column(name = "car_name")    private Set
    
      cars = new HashSet<>();// 必须指定接口实现类    // Map集合属性    @ElementCollection(targetClass = Float.class)    @CollectionTable(name = "salary_inf", joinColumns = @JoinColumn(name = "person_id", nullable = false))    // 指定key的类型    @MapKeyColumn(name = "salary_type")    @MapKeyClass(String.class)    // 映射Map的value    @Column(name = "money")    private Map
     
       payroll = new HashMap<>(); // 必须指定接口实现类    // 映射组件属性，所谓组件的意思是：不是基本数据类型，而是自定义的复合类型，且不是持久化实体    private Address address;    public Address getAddress() {        return address;    }    public void setAddress(Address address) {        this.address = address;    }    public Map
      
        getPayroll() {        return payroll;    }    public void setPayroll(Map
       
         payroll) {        this.payroll = payroll;    }    public String[] getSchools() {        return schools;    }    public void setSchools(String[] schools) {        this.schools = schools;    }    public String getSex() {        return sex;    }    public Set
        
          getCars() { return cars; } public void setCars(Set
         
           cars) { this.cars = cars; } public void setSex(String sex) { this.sex = sex; } public String getProfile() { return profile; } public void setProfile(String profile) { this.profile = profile; } public Person() { } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public String getAlias() { return alias; } public void setAlias(String alias) { this.alias = alias; } public byte[] getImage() { return image; } public void setImage(byte[] image) { this.image = image; } public Date getBirthdate() { return birthdate; } public void setBirthdate(Date birthdate) { this.birthdate = birthdate; } public List
          
            getPets() { return pets; } public void setPets(List
           
             pets) { this.pets = pets; } public void setId(Integer id) { this.id = id; }}
           
          
         
        
       
      
     
    
   

组件类

package com.ydoing.domain;import javax.persistence.Column;import javax.persistence.Embeddable;import org.hibernate.annotations.Parent;@Embeddablepublic class Address {
       @Column(name = "person_province")    private String province;    @Column(name = "person_city")    private String city;    public Address() {    }    // 属于哪个实体组件    @Parent    private Person person;    public Person getPerson() {        return person;    }    public void setPerson(Person person) {        this.person = person;    }    public Address(String province, String city) {        super();        this.province = province;        this.city = city;    }    public String getProvince() {        return province;    }    public void setProvince(String province) {        this.province = province;    }    public String getCity() {        return city;    }    public void setCity(String city) {        this.city = city;    }}

测试：

package com.ydoing.test;import java.util.Arrays;import java.util.List;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.Transaction;import org.hibernate.boot.registry.StandardServiceRegistryBuilder;import org.hibernate.cfg.Configuration;import org.hibernate.service.ServiceRegistry;import com.ydoing.domain.Address;import com.ydoing.domain.Person;public class Main {    public static void main(String[] args) {        Configuration conf = new Configuration();        conf.configure();        // ServiceRegistry serviceRegistry = new        // ServiceRegistryBuilder().applySettings(conf.getProperties())        // .buildServiceRegistry();        ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().applySettings(conf.getProperties())                .build();        SessionFactory factory = conf.buildSessionFactory(serviceRegistry);        Session session = factory.openSession();        Person person = new Person();        person.setName("Jack");        person.setAge(22);        person.setSex("男");        // 不会持久化        person.setAlias("Arron");        // List属性        String[] array = { "cat", "dog", "snake" };        List
   
     pets = Arrays.asList(array);        person.setPets(pets);        // 数组属性        String[] schools = { "清华", "北大" };        person.setSchools(schools);        // Set集合属性        person.getCars().add("奥迪");        person.getCars().add("大众");        // Map属性        person.getPayroll().put("基本工资", (float) 5000);        person.getPayroll().put("绩效", (float) 3000);        person.setAddress(new Address("浙江", "杭州"));        Transaction tx = session.getTransaction();        tx.begin();        session.save(person);        Person p = (Person) session.load(Person.class, 12);        System.out.println(p.getProfile());        tx.commit();        session.close();    }}
   

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