Java去重字符串的两种方法以及java中冒号的使用

package com.removesamestring;
import java.io.BufferedWriter;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

public class Removesamestring {

public static void main(String[] args) {
String text = "test test text text remove remove string string";
System.out.println("strWay1:"+strWay1(text));
System.out.println("strWay2:"+strWay2(text));
}
//方法一
public static String strWay1(String text) {
String[] str = text.split(" ");
if(str.length == 0) {
return null;
}
List<String> list = new ArrayList<String>();
StringBuffer sb = new StringBuffer();
for(int i = 0;i < str.length; i++) {
if(!list.contains(str[i])){
list.add(str[i]);
sb.append(str[i]+" ");
}
}
return sb.toString().substring(0,sb.toString().length()-1);
}
//方法二
public static String strWay2(String text) {
String[] str = text.split(" ");
ArrayList<String> as = new ArrayList<>();
 f:for(int i = 0; i < str.length;i++) {
for(int j = 0; j < as.size();j++ ) {
if(str[i].equals(as.get(j))) {
continue f;//里层的循环continue直接跳出外层循环，继续执行外层循环
}
}
as.add(str[i]);
}
StringBuffer buffer = new StringBuffer();
for(String string : as) {
buffer.append(string+" ");
}
return buffer.toString().substring(0,buffer.toString().lastIndexOf(" "));
}
}

其一: 用来遍历

String[] abc = new String[3]{"a","b","c"};
for （String str : abc）｛
System.out.println(str);    //这个地方的冒号就是遍历abc的集合，取出每一个元素
｝

其二: 三元运算符 Boolean ？ true的内容:false的内容

int a=1;
int b=3;
int i = a>b?3:1;//这个地方的冒号用来选择值，如果a大于b，那么i=3(true)，否则i=1(false)

其三: switch选择

.....
switch (i) {
case "AUS":
URL= GetComposedParameters("globalfund", "AUS", "no", "no", "en-AU", "A4","");
break;
case "GFRP1":
URL= GetComposedParameters("globalfundp1", "", "no", "no", "en-GB", "A4","");
break;
case "NZ":
URL= GetComposedParameters("globalfund", "NZ", "no", "no", "en-NZ", "A4","");
break;
}
return URL;

　　//用于switch选择，当i等于下面的值事，执行后面的操作，然后break跳出; 如果没有break，那么将执行下面的oprate操作，一直到底！