Java循环对bean的属性进行赋值的实现

import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;


public class ObjectUtils {

    
    public static <E> E forEachSetValue(E target, Object value) {
        if (target == null) {
            return target;
        }
        List<Field> fields = new ArrayList<>();
        try {
            // 1.解析出所有的属性
            Field[] declaredFields = target.getClass().getDeclaredFields();
            for (Field declaredField : declaredFields) {
                declaredField.setAccessible(true);
                fields.add(declaredField);
            }
            // 2.把每个属性放入一个集合中
            if (fields.size() <= 0) {
                return target;
            }
            while (fields.get(0).get(target) != null) {
                fields.remove(0);
            }
            Field field = fields.get(0);
            field.set(target, value);
            fields.remove(0);
        } catch (Exception exception) {
            exception.printStackTrace();
        }
        return target;
    }

    
    public static Object forEachGetValue(Object e, int index) {
        try {
            Field[] declaredFields = e.getClass().getDeclaredFields();
            for (Field declaredField : declaredFields) {
                declaredField.setAccessible(true);
            }
            return declaredFields[index].get(e);
        } catch (IllegalAccessException illegalAccessException) {
            illegalAccessException.printStackTrace();
        }
        return e;
    }

    public static int size(Object o) {
        if (o == null) {
            return 0;
        }
        Field[] declaredFields = o.getClass().getDeclaredFields();
        return declaredFields.length;
    }

    
    public static <E> E copyValueFromObject(E target, Object value) {
        if (target == null || value == null) {
            return null;
        }
        Field[] vs = target.getClass().getDeclaredFields();
        Field[] ts = value.getClass().getDeclaredFields();

        try {
            for (int i = 0; i < vs.length; i++) {
                for (int j = 0; j < ts.length; j++) {
                    if (vs[i].getName().equals(ts[j])) {
                        ts[j].set(target, vs[i].get(value));
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return target;
    }

    
    public static <E> E forEachSetValueFromList(E target, List value) {

        if (target == null || value == null || value.size() == 0) {
            return target;
        }
        Field[] ts = target.getClass().getDeclaredFields();
        try {
            for (int i = 0; i < ts.length; i++) {
                ts[i].set(target, value.get(i));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return target;
    }

    
    public static <E> E forEachSetValueFromArray(E target, Object[] value) {

        if (target == null || value == null || value.length == 0) {
            return target;
        }
        Field[] ts = target.getClass().getDeclaredFields();
        try {
            for (int i = 0; i < ts.length; i++) {
                ts[i].set(target, value[i]);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return target;
    }


    public static Object[] getArrayValue(Object o) {
        Field[] declaredFields = o.getClass().getDeclaredFields();
        Object[] result = new Object[declaredFields.length];
        try {
            for (int i = 0; i < declaredFields.length; i++) {
                result[i] = declaredFields[i].get(o);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result;
    }

    public static List getListValue(Object o) {
        Field[] declaredFields = o.getClass().getDeclaredFields();
        List result = new ArrayList(declaredFields.length);
        try {
            for (int i = 0; i < declaredFields.length; i++) {
                result.add(declaredFields[i].get(o));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result;
    }
}