【hibernate】自定义转换器

【hibernate】自定义转换器

转载：https://www.cnblogs.com/yangchongxing/p/10398255.html

1、转换基本属性

package cn.ycx.study.hibernate.bean;

import java.math.BigDecimal;
import java.util.Currency;

public class Money {
    public static final String SPLIT_SYMBOL = " ";
    protected BigDecimal value;
    protected Currency currency;
    public Money(BigDecimal value, Currency currency) {
        this.value = value;
        this.currency = currency;
    }
    public BigDecimal getValue() {
        return value;
    }
    public void setValue(BigDecimal value) {
        this.value = value;
    }
    public Currency getCurrency() {
        return currency;
    }
    public void setCurrency(Currency currency) {
        this.currency = currency;
    }
    @Override
    public String toString() {
        return getValue().toString() + SPLIT_SYMBOL + getCurrency();
    }
    public static Money fromString(String s) {
        String[] split = s.split(SPLIT_SYMBOL);
        return new Money(new BigDecimal(split[0]), Currency.getInstance(split[1]));
    }
}

转换器实现

package cn.ycx.study.hibernate.converter;

import javax.persistence.AttributeConverter;

import cn.ycx.study.hibernate.bean.Money;

public class MoneyConverter implements AttributeConverter<Money, String> {

    @Override
    public String convertToDatabaseColumn(Money attribute) {
        return attribute.toString();
    }

    @Override
    public Money convertToEntityAttribute(String dbData) {
        return Money.fromString(dbData);
    }

}

实体对象

package cn.ycx.study.hibernate.entity;

import javax.persistence.Convert;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

import cn.ycx.study.hibernate.bean.Money;
import cn.ycx.study.hibernate.converter.MoneyConverter;
@Entity
@org.hibernate.annotations.DynamicInsert
@org.hibernate.annotations.DynamicUpdate
public class User {
    @Id
    @GeneratedValue(generator="id_generator")
    protected long id;
    public long getId() {
        return id;
    }
    public void setId(long id) {
        this.id = id;
    }
    @Convert(converter = MoneyConverter.class,disableConversion=false)
    protected Money money;
    public Money getMoney() {
        return money;
    }
    public void setMoney(Money money) {
        this.money = money;
    }
}

测试

    @Test
    public void testInsert() {
        User u = new User();
        u.setMoney(new Money(new BigDecimal(10), Currency.getInstance(Locale.CHINA)));
        this.session.persist(u);
        assertTrue( true );
    }

2、转换组件的属性

package cn.ycx.study.hibernate.entity;

import javax.persistence.Convert;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

import cn.ycx.study.hibernate.bean.Money;
import cn.ycx.study.hibernate.converter.MoneyConverter;
import cn.ycx.study.hibernate.converter.ZipcodeConverter;
@Entity
@org.hibernate.annotations.DynamicInsert
@org.hibernate.annotations.DynamicUpdate
public class User {
    @Id
    @GeneratedValue(generator="id_generator")
    protected long id;
    public long getId() {
        return id;
    }
    public void setId(long id) {
        this.id = id;
    }
    //转换基本属性
    @Convert( converter = MoneyConverter.class, disableConversion = false )
    protected Money money;
    public Money getMoney() {
        return money;
    }
    public void setMoney(Money money) {
        this.money = money;
    }
    //转换组件属性
    @Convert( converter = ZipcodeConverter.class, attributeName = "zipcode")
    protected Address address;
    public Address getAddress() {
        return address;
    }
    public void setAddress(Address address) {
        this.address = address;
    }
}

attributeName 声明了可嵌入 Address 类的 zipcode 属性。这一设置支持圆点属性路径，如果 zipcode 是 可嵌入 City 的属性，则要使用嵌套路径 city.zipcode 类引用它

组件

package cn.ycx.study.hibernate.entity;
import javax.persistence.Embeddable;
import javax.validation.constraints.NotNull;

import cn.ycx.study.hibernate.bean.Zipcode;
@Embeddable
public class Address {
    @NotNull
    protected String street;
    @NotNull
    protected Zipcode zipcode;
    @NotNull
    protected City city;
    public Address() {
    }
    public Address(String street, Zipcode zipcode, City city) {
        this.street = street;
        this.zipcode = zipcode;
        this.city = city;
    }
    public String getStreet() {
        return street;
    }
    public void setStreet(String street) {
        this.street = street;
    }
    public Zipcode getZipcode() {
        return zipcode;
    }
    public void setZipcode(Zipcode zipcode) {
        this.zipcode = zipcode;
    }
    public City getCity() {
        return city;
    }
    public void setCity(City city) {
        this.city = city;
    }
}

package cn.ycx.study.hibernate.bean;

public abstract class Zipcode {
    protected String symbol;
    protected String value;
    public Zipcode(String symbol, String value) {
        this.symbol = symbol;
        this.value = value;
    }
    public String getSymbol() {
        return symbol;
    }
    public void setSymbol(String symbol) {
        this.symbol = symbol;
    }
    public String getValue() {
        return value;
    }
    public void setValue(String value) {
        this.value = value;
    }
}

package cn.ycx.study.hibernate.bean;

public class ChinaZipcode extends Zipcode {
    public ChinaZipcode(String symbol, String value) {
        super(symbol, value);
    }
}

package cn.ycx.study.hibernate.bean;

public class UsaZipcode extends Zipcode {
    public UsaZipcode(String symbol, String value) {
        super(symbol, value);
    }
}

转换器

package cn.ycx.study.hibernate.converter;

import javax.persistence.AttributeConverter;

import cn.ycx.study.hibernate.bean.ChinaZipcode;
import cn.ycx.study.hibernate.bean.UsaZipcode;
import cn.ycx.study.hibernate.bean.Zipcode;

public class ZipcodeConverter implements AttributeConverter<Zipcode, String> {

    @Override
    public String convertToDatabaseColumn(Zipcode attribute) {
        return attribute.getValue();
    }

    @Override
    public Zipcode convertToEntityAttribute(String dbData) {
        if (dbData.length() == 6) {
            return new ChinaZipcode("CN", dbData);
        } else if (dbData.length() == 5) {
            return new UsaZipcode("US", dbData);
        }
        throw new IllegalArgumentException("Unsupported zipcode in database...");
    }

}