jdk7 中Collections.sort 异常

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Collections.sort 异常

java.lang.IllegalArgumentException: Comparison method violates its general contract!        at java.util.TimSort.mergeHi(TimSort.java:868)        at java.util.TimSort.mergeAt(TimSort.java:485)        at java.util.TimSort.mergeForceCollapse(TimSort.java:426)        at java.util.TimSort.sort(TimSort.java:223)        at java.util.TimSort.sort(TimSort.java:173)        at java.util.Arrays.sort(Arrays.java:659)        at java.util.Collections.sort(Collections.java:217)

代码如下：

Collections.sort(values, new Comparator<Map.Entry<String, Float>>() {    <span style="white-space:pre"></span>public int compare(Map.Entry<String, Float> o1, Map.Entry<String, Float> o2) {  <span style="white-space:pre"></span>return (o2.getValue() > o1.getValue() ? 1 : -1);   }   });

是对一个Map数组进行排序，更新了jdk版本后报以上异常，查询了先关资料后，修改了代码如下：

Collections.sort(values, new Comparator<Map.Entry<String, Float>>() {    public int compare(Map.Entry<String, Float> o1, Map.Entry<String, Float> o2) {  return o2.getValue().compareTo(o1.getValue());}   });

异常解决，参考链接：

http://stackoverflow.com/questions/10234038/compare-method-throw-exception-comparison-method-violates-its-general-contract

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