Java 多字段排序Comparator(兼容Date,Integer,Doubel,Long)

Java 反射类：ReflexUtil

public class ReflexUtil {
    static Logger logger = LoggerFactory.getLogger(ReflexUtil.class);

    //getMethod
    static public Object invokeMethod(String propertiesName, Object object) {
        try {
            if(object==null) return null;
            if (!propertiesName.contains(".")) {
                String methodName = "get"+getMethodName(propertiesName);
                Method method = object.getClass().getMethod(methodName);
                return method.invoke(object);
            }
            String methodName = "get"+getMethodName(propertiesName.substring(0,propertiesName.indexOf(".")));
            Method method = object.getClass().getMethod(methodName);
            return invokeMethod(propertiesName.substring(propertiesName.indexOf(".")+1), method.invoke(object));

        } catch (Exception e) {
            logger.error(e.toString(), e);
            return null;
        }
    }

    private static String getMethodName(String fildeName) {
        byte[] items = fildeName.getBytes();
        items[0] = (byte) ((char) items[0] - 'a' + 'A');
        return new String(items);
    }

    public static void main(String args[]) {
        Video video = new Video();
        Album album = new Album();
        album.setAlbumId(346l);
        video.setAlbum(album);
        video.setVideoId(126l);
        System.out.println(ReflexUtil.invokeMethod("album.albumId", video));
    }
}

Java 对象排序 ： CompareUtil ()

package com.gochinatv.vrs.framework.util;

import com.alibaba.fastjson.JSONObject;
import com.gochinatv.vrs.framework.bean.LabelAlbum;
import com.gochinatv.vrs.framework.bean.Video;

import java.util.*;

/**
 * Created by shhao
 * Date: 14-5-6.
 * Time:下午4:48
 */
public class CompareUtil {

    //sort 1正序 -1 倒序  filed 多字段排序
    public static <T> Comparator createComparator(int sort, String... filed) {
        return new ImComparator(sort, filed);
    }

    public static class ImComparator implements Comparator {
        int sort = 1;
        String[] filed;

        public ImComparator(int sort, String... filed) {
            this.sort = sort == -1 ? -1 : 1;
            this.filed = filed;
        }

        @Override
        public int compare(Object o1, Object o2) {
            int result = 0;
            for (String file : filed) {
                Object value1 = ReflexUtil.invokeMethod(file, o1);
                Object value2 = ReflexUtil.invokeMethod(file, o2);
                if (value1 == null || value2 == null) {
                    continue;
                }
                if (value1 instanceof Integer) { //Integer整数序排序
                    int v1 = Integer.valueOf(value1.toString());
                    int v2 = Integer.valueOf(value2.toString());
                    if (v1 == v2) continue;
                    if (sort == 1) {
                        return v1 - v2;
                    } else if (sort == -1) {
                        return v2 - v1;
                    }
                } else if (value1 instanceof Date) {  //Date类型排序
                    Date d1 = (Date) value1;
                    Date d2 = (Date) value2;
                    if (d1.compareTo(d2) == 0) continue;
                    if (sort == 1) {
                        return d1.compareTo(d2);
                    } else if (sort == -1) {
                        return d2.compareTo(d1);
                    }
                } else if (value1 instanceof Long) { //Long排序
                    long v1 = Long.valueOf(value1.toString());
                    long v2 = Long.valueOf(value2.toString());
                    if (v1 == v2) continue;
                    if (sort == 1) {
                        return v1 > v2 ? 1 : -1;
                    } else if (sort == -1) {
                        return v2 > v1 ? 1 : -1;
                    }
                } else if (value1 instanceof Double) { //Double排序
                    Double v1 = Double.valueOf(value1.toString());
                    Double v2 = Double.valueOf(value2.toString());
                    if (v1 == v2) continue;
                    if (sort == 1) {
                        return v1 > v2 ? 1 : -1;
                    } else if (sort == -1) {
                        return v2 > v1 ? 1 : -1;
                    }
                }

            }

            return result;
        }
    }

    public static void main(String args[]) {
        Video label1 = new Video();
        label1.setDisplayOrder(1);
        label1.setCreateTime(DateUtils.convert("2014-01-01"));
        Video label2 = new Video();
        label2.setDisplayOrder(3);
        label2.setCreateTime(DateUtils.convert("2014-01-02"));
        Video label3 = new Video();
        label3.setDisplayOrder(2);
        label3.setCreateTime(DateUtils.convert("2014-01-03"));
        Video label4 = new Video();
        label4.setDisplayOrder(2);
        label4.setCreateTime(DateUtils.convert("2014-01-01"));
        Video label5 = new Video();
        label5.setDisplayOrder(4);
        label5.setCreateTime(DateUtils.convert("2014-01-05"));
        List<Video> list = new ArrayList<Video>();
        list.add(label1);
        list.add(label2);
        list.add(label3);
        list.add(label4);
        list.add(label5);
        Collections.sort(list, CompareUtil.createComparator(1, "createTime", "displayOrder"));
        for (int i = 0; i < list.size(); i++) {
            Video labelAlbum = list.get(i);
            System.out.println("displayorder:" + labelAlbum.getDisplayOrder() + "  sequence：" + DateUtils.convert(labelAlbum.getCreateTime()));
        }
    }
}