JavaScript有Array.join()

js>["Bill","Bob","Steve"].join(" and ")
Bill and Bob and Steve

Java有这样的东西吗?我知道我可以用StringBuilder自己拼凑一些东西:

static public String join(List<String> list, String conjunction)
{
   StringBuilder sb = new StringBuilder();
   boolean first = true;
   for (String item : list)
   {
      if (first)
         first = false;
      else
         sb.append(conjunction);
      sb.append(item);
   }
   return sb.toString();
}

. .但是如果像这样的东西已经是JDK的一部分,那么这样做就没有意义了。


当前回答

在纯JDK中有一种有趣的方法:

String[] array = new String[] { "Bill", "Bob", "Steve","[Bill]","1,2,3","Apple ][" };
String join = " and ";

String joined = Arrays.toString(array).replaceAll(", ", join)
        .replaceAll("(^\\[)|(\\]$)", "");

System.out.println(joined);

输出:

比尔、鲍勃、史蒂夫、[比尔]、1,2,3和苹果][


一个不太完美也不太有趣的方式!

String[] array = new String[] { "7, 7, 7","Bill", "Bob", "Steve", "[Bill]",
        "1,2,3", "Apple ][" };
String join = " and ";

for (int i = 0; i < array.length; i++) array[i] = array[i].replaceAll(", ", "~,~");
String joined = Arrays.toString(array).replaceAll(", ", join)
        .replaceAll("(^\\[)|(\\]$)", "").replaceAll("~,~", ", ");

System.out.println(joined);

输出:

7,7,7和比尔,鲍勃,史蒂夫和[比尔],1,2,3和苹果][

其他回答

不,在标准Java API中没有这样方便的方法。

毫不奇怪,Apache Commons在它们的StringUtils类中提供了这样一个东西,以防您不想自己编写它。

另一个解,它是另一个答案的变体

public static String concatStringsWSep(Iterable<String> strings, String separator) {
    Iterator<String> it = strings.iterator();
    if( !it.hasNext() ) return "";
    StringBuilder sb = new StringBuilder(it.next());
    while( it.hasNext()) {
        sb.append(separator).append(it.next());
    }
    return sb.toString();                           
}

在纯JDK中有一种有趣的方法:

String[] array = new String[] { "Bill", "Bob", "Steve","[Bill]","1,2,3","Apple ][" };
String join = " and ";

String joined = Arrays.toString(array).replaceAll(", ", join)
        .replaceAll("(^\\[)|(\\]$)", "");

System.out.println(joined);

输出:

比尔、鲍勃、史蒂夫、[比尔]、1,2,3和苹果][


一个不太完美也不太有趣的方式!

String[] array = new String[] { "7, 7, 7","Bill", "Bob", "Steve", "[Bill]",
        "1,2,3", "Apple ][" };
String join = " and ";

for (int i = 0; i < array.length; i++) array[i] = array[i].replaceAll(", ", "~,~");
String joined = Arrays.toString(array).replaceAll(", ", join)
        .replaceAll("(^\\[)|(\\]$)", "").replaceAll("~,~", ", ");

System.out.println(joined);

输出:

7,7,7和比尔,鲍勃,史蒂夫和[比尔],1,2,3和苹果][

你可以使用apache公共库,它有一个StringUtils类和一个join方法。

查看这个链接:https://commons.apache.org/proper/commons-lang/javadocs/api.2.0/org/apache/commons/lang/StringUtils.html

请注意,上面的链接可能会随着时间的推移而过时,在这种情况下,你可以在网上搜索“apache commons StringUtils”,它应该可以让你找到最新的引用。

(从这个线程引用) Java等价的c# String.Format()和String.Join()

你可以这样做:

String aToString = java.util.Arrays.toString(anArray);
// Do not need to do this if you are OK with '[' and ']'
aToString = aToString.substring(1, aToString.length() - 1);

或者单行语句(仅当不需要'['和']'时)

String aToString = java.util.Arrays.toString(anArray).substring(1).replaceAll("\\]$", "");

希望这能有所帮助。