BeanUtils自定义converter和BeanCopier自定义converter

问题

Form类里面有Enum类，po存到数据库时，想存枚举类的code，需要将Enum转换为String(code)

src class, Form

@Data
public class BaseInfoForm implements Serializable {
    private static final long serialVersionUID = 2261054116525535919L;
    
    private String contractName;
    private ContractTypeEnum contractType;
}

target class, po

public class TbContManBasic extends Model {

    private static final long serialVersionUID = 1L;

	private String contractName;
    private String contractType;

ContractTypeEnum class, Enum

@Getter
public enum ContractTypeEnum {
    FRAMEWORK_AGREEMENT("FRAMEWORK_AGREEMENT", "框架协议"),
    FORMAL_CONTRACT("FORMAL_CONTRACT", "正式合同"),
    INVESTMENT_COOPERATION_AGREEMENT("INVESTMENT_COOPERATION_AGREEMENT", "投资合作协议"),
    SUPPLEMENTAL_AGREEMENT("SUPPLEMENTAL_AGREEMENT", "补充协议"),
    TERMINATION_AGREEMENT("TERMINATION_AGREEMENT", "终止协议"),
    BIG_ISSUES("BIG_ISSUES", "重大事项"),
    INTENTION_AGREEMENT("INTENTION_AGREEMENT", "意向协议"),
    GOVERNMENT_COOPERATION_AGREEMENT("GOVERNMENT_COOPERATION_AGREEMENT", "政府合作协议"),
    OTHER_CONT("OTHER_CONT", "其他")
    ;

    ContractTypeEnum(String code, String message) {
        this.code = code;
        this.message = message;
    }

    private String code;
    private String message;


    /**
     * 重写toString()返回code
     * @return
     */
    @Override
    public String toString() {
        return this.code;
    }
}

要重写枚举类的toString()方法用来获取code，因为Enum类只有一个toString()方法可以重写

解决办法

1. apache BeanUtils converter（不推荐，速度慢）

1.1 导入依赖

        
            commons-beanutils
            commons-beanutils
            1.9.3
        

1.2 编写转换器

import org.apache.commons.beanutils.Converter;

public class Enum2StringConverter2 implements Converter{

    @Override
    public String convert(Class aClass, Object o) {
        try {
            return ((Enum) o).toString();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
}

1.3 使用

import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.beanutils.ConvertUtils;

		//当有ContractTypeEnum这个类时，使用转换器转换ContractTypeEnum这个枚举类，转换为String，不影响其他类型转换
        ConvertUtils.register(new Enum2StringConverter2(), ContractTypeEnum.class);
        
        //tbContManBasic是target, manContractForm.getBaseInfoForm()是src
        BeanUtils.copyProperties(tbContManBasic, manContractForm.getBaseInfoForm());

2. BeanCopier converter

2.1 编写转换器

public class Enum2StringConverter implements Converter {

    @Override
    public Object convert(Object o, Class aClass, Object o1) {
        if (o instanceof Enum) {
            return o.toString();
        }else {
            return o;
        }
    }
}

BeanCopier使用这个转换器时完全按照这个转换器来转化，所以，如果src和target其他属性都一样就直接返回

2.2 使用

		//设置为true才按照自定义转换器来转化两个类
		BeanCopier copier = BeanCopier.create(BaseInfoForm.class, TbContManBasic.class, true);
        Enum2StringConverter converter = new Enum2StringConverter();
        
        //manContractForm.getBaseInfoForm(): src, tbContManBasic: target, converter:转换器
        copier.copy(manContractForm.getBaseInfoForm(), tbContManBasic, converter);