这月新晋级奶爸了,代码写的都少了哈哈~~~
如题,当我们业务有涉及到复杂的数据组装和计算时,我都喜欢使用传统的JavaBean装载业务数据。里面可以写一些该业务的专有运算方法,又不会污染基础Model类,后续阅读业务代码也会清晰一点。
废话不多说,上石马:
import com.jfinal.plugin.activerecord.Record; import java.beans.Introspector; import java.beans.PropertyDescriptor; import java.lang.reflect.Constructor; import java.util.ArrayList; import java.util.List; import java.util.Map; public class RecordToBean { public static <T> T to(Record r, Class<T> clazz) { try { T ret = clazz.getDeclaredConstructor().newInstance(); PropertyDescriptor[] pds = Introspector.getBeanInfo(clazz, Object.class).getPropertyDescriptors(); Map<String, Object> columns = r.getColumns(); for (PropertyDescriptor pd : pds) { String key = pd.getName(); Object value = columns.get(key); pd.getWriteMethod().invoke(ret, value); } return ret; }catch (Exception e){ throw new RuntimeException(e); } } public static <T> List<T> to(List<Record> list, Class<T> clazz) { try { Constructor<T> constructor = clazz.getDeclaredConstructor(); PropertyDescriptor[] pds = Introspector.getBeanInfo(clazz, Object.class).getPropertyDescriptors(); List<T> ret = new ArrayList<>(list.size()); for (Record r : list) { T obj = constructor.newInstance(); for (PropertyDescriptor pd : pds) { String key = pd.getName(); Object value = r.getColumns().get(key); pd.getWriteMethod().invoke(obj, value); } ret.add(obj); } return ret; }catch (Exception e){ throw new RuntimeException(e); } } }
测试:
public static class MyBean{ private String a; public void setA(String a) { this.a = a; } private BigDecimal b; public void setB(BigDecimal b) { this.b = b; } //get... @Override public String toString() { return "MyBean{" + "a='" + a + '\'' + ", b=" + b + '}'; } } public static void main(String[] args) { Record r = new Record(); r.set("a", "A"); r.set("b", new BigDecimal("888")); MyBean t = RecordToBean.to(r, MyBean.class); System.out.println(t); List<Record> list = new ArrayList<>(); list.add(r); list.add(r); List<MyBean> rs = RecordToBean.to(list, MyBean.class); System.out.println(rs); }
结果:
非常方便!
常见用法: List<Record> list = Db.templateByString(sql, Kv.create()).find(); List<MyBean> rs = RecordToBean.to(list, MyBean.class);