java中两个对象浅拷贝


开发中经常需要复制对象的属性,一般情况下都为浅拷贝。在这里写了一个简单实现:

public class CopyByName {
	
	public static void copyByName(Object src, Object target) {
        if (src == null || target == null) {
            return;
        }
        try {
            Map srcFieldMap= getAssignableFieldsMap(src);
            Map targetFieldMap = getAssignableFieldsMap(target);
            for (String srcFieldName : srcFieldMap.keySet()) {
                Field srcField = srcFieldMap.get(srcFieldName);
                if (srcField == null) {
                    continue;
                }
                // 变量名需要相同
                if (!targetFieldMap.keySet().contains(srcFieldName)) {
                    continue;
                }
                Field targetField = targetFieldMap.get(srcFieldName);
                if (targetField == null) {
                    continue;
                }
                // 类型需要相同
                if (!srcField.getType().equals(targetField.getType())) {
                    continue;
                }

                targetField.set(target,srcField.get(src));
            }
        }catch (Exception e) {
            // 异常
        }
        return ;
    }

    private static Map getAssignableFieldsMap(Object obj) {
        if (obj == null) {
            return new HashMap();
        }
        Map fieldMap = new HashMap();
        for (Field field : obj.getClass().getDeclaredFields()) {
            // 过滤不需要拷贝的属性
            if (Modifier.isStatic(field.getModifiers()) 
                 || Modifier.isFinal(field.getModifiers())) {
                continue;
            }
            field.setAccessible(true);
            fieldMap.put(field.getName(), field);
        }
        return fieldMap;
    }
}

  使用方法:

  Test a = new Test();
  Test b = new Test();
   b.setField1("11");

  CopyByName.copyByName(b, a); //复制b到a