# Lambda 表达å¼
在Java8以å‰ï¼Œä½¿ç”¨`Collections`çš„sort方法对å—符串排åºçš„写法：
```java
List names = Arrays.asList("dabin", "tyson", "sophia");
Collections.sort(names, new Comparator() {
@Override
public int compare(String a, String b) {
return b.compareTo(a);
}
});
```
Java8 推è使用lambda表达å¼ï¼Œç®€åŒ–è¿™ç§å†™æ³•ã€‚
```java
List names = Arrays.asList("dabin", "tyson", "sophia");
Collections.sort(names, (String a, String b) -> b.compareTo(a)); //简化写法一
names.sort((a, b) -> b.compareTo(a)); //简化写法二，çœç•¥å…¥å‚类型，Java ç¼–è¯‘å™¨èƒ½å¤Ÿæ ¹æ®ç±»åž‹æŽ¨æ–机制判æ–出å‚数类型
```
å¯ä»¥çœ‹åˆ°ä½¿ç”¨lambda表示å¼ä¹‹åŽï¼Œä»£ç å˜å¾—很简çŸå¹¶ä¸”易于阅读。