根据条件创建不同的POJO子对象，但共享公共字段

// 父类
public class BasePOJO {
    private String sharedField;

    public String getSharedField() {
        return sharedField;
    }

    public void setSharedField(String sharedField) {
        this.sharedField = sharedField;
    }
}

// 子类1
public class SubPOJO1 extends BasePOJO {
    private String specificField1;

    public String getSpecificField1() {
        return specificField1;
    }

    public void setSpecificField1(String specificField1) {
        this.specificField1 = specificField1;
    }
}

// 子类2
public class SubPOJO2 extends BasePOJO {
    private String specificField2;

    public String getSpecificField2() {
        return specificField2;
    }

    public void setSpecificField2(String specificField2) {
        this.specificField2 = specificField2;
    }
}