场景：Java 类 需 重新排序，有时升序、有时倒叙，有时是多字段排序
代码：
package GenericTest;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
/**
* [简述]:List通用排序工具类
* User: xyj
* Date: 2016/07/03
* Created with IntelliJ IDEA.
*/
public class ListSortUtils {
private static final String SORT_ASC = "asc";
private static final String SORT_DESC = "desc";
/**
* [简述]： 对List数组排序
* @param list 源数据 排序集合
* @param sort 升序 还是 降序，默认升序
* @return List
*/
public static List> sort(List> list,final String sort){
Collections.sort(list, new Comparator() {
@Override
public int compare(Object o1, Object o2) {
int ret = String.valueOf(o1).compareTo(String.valueOf(o2));;
if(null != sort && SORT_DESC.equalsIgnoreCase(sort)){
return -ret;
}else{
return ret;
}
}
});
return list;
}
/**
*[简述]: List 泛型 排序
* @param list 源数据 排序集合
* @param field 排序的数据字段名称
* @param sort 升序 还是 降序，默认升序
* @param 泛型T
* @return List
*/
public static List sort(List list,final String field,final String sort){
Collections.sort(list, new Comparator() {
@Override
public int compare(T o1, T o2) {
int ret = 0;
try {
Method method1 = o1.getClass().getDeclaredMethod(getMethodName(field),null);
Method method2 = o1.getClass().getDeclaredMethod(getMethodName(field), null);
ret = method1.invoke(o1).toString().compareTo( method2.invoke(o2).toString());
} catch (NoSuchMethodException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
}
if(null != sort && SORT_DESC.equalsIgnoreCase(sort)){
return -ret;
}else{
return ret;
}
}
});
return list;
}
/**
*[简述]: List 泛型 排序
* @param list 源数据 排序集合
* @param fields 排序的数据字段名称
* @param sorts 升序 还是 降序
* @param 泛型T
* @return List
*/
public static List sort(List list,final String [] fields,final String [] sorts){
if(null != fields && fields.length > 0){
for(int index = 0;index < fields.length;index ++){
String sortRule = SORT_ASC;
if(null != sorts && sorts.length >= index && null != sorts[index]){
sortRule = sorts[index];
}
final String sort = sortRule;
final String field = fields[index];
Collections.sort(list, new Comparator() {
@Override
public int compare(T o1, T o2) {
int ret = 0;
try {
Method method1 = o1.getClass().getDeclaredMethod(getMethodName(field),null);
Method method2 = o1.getClass().getDeclaredMethod(getMethodName(field), null);
ret = method1.invoke(o1).toString().compareTo( method2.invoke(o2).toString());
} catch (NoSuchMethodException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
}
if(null != sort && SORT_DESC.equalsIgnoreCase(sort)){
return -ret;
}else{
return ret;
}
}
});
}
}
return list;
}
private static String getMethodName(String str){
StringBuffer name = new StringBuffer();
name = name.append("get").append(firstLetterToCapture(str));
return name.toString();
}
private static String firstLetterToCapture(String name){
char[] arr = name.toCharArray();
arr[0] -= 32;
return String.valueOf(arr);
}
}
