package com.ebizserve.tarket.service.command;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import org.apache.log4j.Logger;
public class Test {
private static Logger logger = Logger.getLogger(Test.class);
public static void main(String[] args) {
int index;
Set<Float> set = new HashSet<Float>();
List<Float> list = new ArrayList<Float>();
set.add(68.1f );
set.add(68.0f );
set.add(68.3f );
set.add(68.2f );
for (Iterator it = set.iterator(); it.hasNext();) {
list.add((Float) it.next());
}
// Collections.sort()方法用於自然排序List對象;
Collections.sort(list);
for (Float l : list) {
logger.info("自然排序:" + l);
}
logger.info("-------------------------------------");
// Collections.reverse()方法用於倒轉排序List對象;
Collections.reverse(list);
for (Float l : list) {
logger.info("倒轉排序:" + l);
}
// Collections.binarySearch()方法檢索對象所在位置;
int k = Collections.binarySearch(list,
new Float(68.0));
// list.indexOf()方法檢索對象所以位置;
// int k = list.indexOf(68.0f );
logger.info("k---------" + k);
index = k + 1;
logger.info("index---------" + index);
}
}
Collections.binarySearch()方法查找的索引位置不正確,後改爲用List.indexOf()方法;請同志們分析下。