blocks|key|755034|text|尝试使用Arrays.toString重载方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|755035|或者，尝试下面的通用实现：|755036|public+static+void+main(String...+args)+throws+Exception+{

++++String[]+array+=+{"ABC",+"XYZ",+"PQR"};

++++System.out.println(new+Test().join(array,+",+"));
}

public+<T>+String+join(T[]+array,+String+cement)+{
++++StringBuilder+builder+=+new+StringBuilder();

++++if(array+==+null+%7C%7C+array.length+==+0)+{
++++++++return+null;
++++}

++++for+(T+t+:+array)+{
++++++++builder.append(t).append(cement);
++++}

++++builder.delete(builder.length()+-+cement.length(),+builder.length());

++++return+builder.toString();
}|code-block|syntax|javascript|755037|entityMap|0|LINK|mutability|MUTABLE|url|http://download.oracle.com/javase/6/docs/api/java/util/Arrays.html#toString%2528java.lang.Object%255B%255D%2529^0|4|F|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]]|C|$]]|$1|D|3|E|5|6|7|W|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|X|8|@]|9|@]|C|$I|J]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]]]

Try the <a href="http://download.oracle.com/javase/6/docs/api/java/util/Arrays.html#toString%28java.lang.Object%5B%5D%29" rel="noreferrer">Arrays.toString</a> overloaded methods.

Or else, try this below generic implementation:

<pre><code>public static void main(String... args) throws Exception {

 String[] array = {"ABC", "XYZ", "PQR"};

 System.out.println(new Test().join(array, ", "));
}

public &lt;T&gt; String join(T[] array, String cement) {
 StringBuilder builder = new StringBuilder();

 if(array == null || array.length == 0) {
 return null;
 }

 for (T t : array) {
 builder.append(t).append(cement);
 }

 builder.delete(builder.length() - cement.length(), builder.length());

 return builder.toString();
}
</code></pre>

blocks|key|970689|text|使用Apache+commons+StringUtils.join()。它接受一个数组作为参数(也有Iterable和Iterator参数的重载)，并在每个元素上调用toString()+(如果它不为null)以获得每个元素的字符串表示。然后，如果指定了一个分隔符，则将每个元素字符串表示连接到一个字符串中：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|970690|String+joinedString+=+StringUtils.join(new+Object[]{"a",+"b",+1},+"-");
System.out.println(joinedString);|code-block|syntax|javascript|970691|产生：|970692|a-b-1|970693|entityMap|0|LINK|mutability|MUTABLE|url|https://commons.apache.org/proper/commons-lang/apidocs/org/apache/commons/lang3/StringUtils.html#join(java.lang.Object[],%2520java.lang.String))^0|H|I|1E|8|1N|8|2B|A|H|I|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]|$9|Z|A|10|B|C]|$9|11|A|12|B|C]|$9|13|A|14|B|C]]|D|@$9|15|A|16|1|17]]|E|$]]|$1|F|3|G|5|H|7|18|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|19|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|1A|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|1B|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]]]

Use Apache commons <a href="https://commons.apache.org/proper/commons-lang/apidocs/org/apache/commons/lang3/StringUtils.html#join(java.lang.Object[],%20java.lang.String)"><code>StringUtils.join()</code></a>. It takes an array, as a parameter (and also has overloads for <code>Iterable</code> and <code>Iterator</code> parameters) and calls <code>toString()</code> on each element (if it is not null) to get each elements string representation. Each elements string representation is then joined into one string with a separator in between if one is specified:

<pre><code>String joinedString = StringUtils.join(new Object[]{"a", "b", 1}, "-");
System.out.println(joinedString);
</code></pre>

Produces:

<pre><code>a-b-1
</code></pre>

blocks|key|970735|text|你可以这样做，给定一个原始类型的数组a：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|970736|StringBuffer+result+=+new+StringBuffer();
for+(int+i+=+0;+i+<+a.length;+i%2B%2B)+{
+++result.append(+a[i]+);
+++//result.append(+optional+separator+);
}
String+mynewstring+=+result.toString();|code-block|syntax|javascript|970737|entityMap^0|I|1|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

You could do this, given an array <code>a</code> of primitive type:

<pre><code>StringBuffer result = new StringBuffer();
for (int i = 0; i &lt; a.length; i++) {
 result.append( a[i] );
 //result.append( optional separator );
}
String mynewstring = result.toString();
</code></pre>

blocks|key|755164|text|我喜欢使用Google's+Guava+Joiner来做这件事，例如：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|755165|Joiner.on(",+").skipNulls().join("Harry",+null,+"Ron",+"Hermione");|code-block|syntax|javascript|755166|将生成与以下内容相同的字符串：|755167|new+String("Harry,+Ron,+Hermione");|755168|ETA:+Java+8现在也有类似的支持：|755169|String.join(",+",+"Harry",+"Ron",+"Hermione");|755170|我看不到对跳过null值的支持，但这很容易解决。|755171|entityMap|0|LINK|mutability|MUTABLE|url|http://guava-libraries.googlecode.com/svn/trunk/javadoc/com/google/common/base/Joiner.html^0|5|L|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@$A|11|B|12|1|13]]|C|$]]|$1|D|3|E|5|F|7|14|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|15|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|16|8|@]|9|@]|C|$G|H]]|$1|M|3|N|5|6|7|17|8|@]|9|@]|C|$]]|$1|O|3|P|5|F|7|18|8|@]|9|@]|C|$G|H]]|$1|Q|3|R|5|6|7|19|8|@]|9|@]|C|$]]|$1|S|3|-4|5|6|7|1A|8|@]|9|@]|C|$]]]|T|$U|$5|V|W|X|C|$Y|Z]]]]

I like using <a href="http://guava-libraries.googlecode.com/svn/trunk/javadoc/com/google/common/base/Joiner.html" rel="noreferrer">Google's Guava Joiner</a> for this, e.g.:

<pre><code>Joiner.on(", ").skipNulls().join("Harry", null, "Ron", "Hermione");
</code></pre>

would produce the same String as:

<pre><code>new String("Harry, Ron, Hermione");
</code></pre>

ETA: Java 8 has similar support now:

<pre><code>String.join(", ", "Harry", "Ron", "Hermione");
</code></pre>

Can't see support for skipping null values, but that's easily worked around.

blocks|key|755243|text|尝试Arrays.deepToString方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|755244|返回指定数组的“深层内容”的字符串表示形式。如果数组包含其他数组作为元素，则字符串表示包含其内容，依此类推。此方法用于将多维数组转换为字符串|755245|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Arrays.html#deepToString%2528java.lang.Object%255B%255D%2529^0|2|J|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@$A|O|B|P|1|Q]]|C|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@]|C|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|C|$]]]|G|$H|$5|I|J|K|C|$L|M]]]]

Try the <a href="http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Arrays.html#deepToString%28java.lang.Object%5B%5D%29">Arrays.deepToString</a> method.

Returns a string representation of the "deep contents" of the specified
 array. If the array contains other arrays as elements, the string
 representation contains their contents and so on. This method is
 designed for converting multidimensional arrays to strings

blocks|key|970875|text|如果你知道数组有多少元素，一种简单的方法是这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|970876|String+appendedString+=+""+%2B+array[0]+%2B+""+%2B+array[1]+%2B+""+%2B+array[2]+%2B+""+%2B+array[3];+|code-block|syntax|javascript|970877|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If you know how much elements the array has, a simple way is doing this:

<pre><code>String appendedString = "" + array[0] + "" + array[1] + "" + array[2] + "" + array[3]; 
</code></pre>

blocks|key|755335|text|String[]+strings+=+new+String[25000];
for+(int+i+=+0;+i+<+25000;+i%2B%2B)+strings[i]+=+'1234567';

String+result;
result+=+"";
for+(String+s+:+strings)+result+%2B=+s;
//linear+%2B:+5s

result+=+"";
for+(String+s+:+strings)+result+=+result.concat(s);
//linear+.concat:+2.5s

result+=+String.join("",+strings);
//Java+8+.join:+3ms

Public+String+join(String+delimiter,+String[]+s)
{
++++int+ls+=+s.length;
++++switch+(ls)
++++{
++++++++case+0:+return+"";
++++++++case+1:+return+s[0];
++++++++case+2:+return+s[0].concat(delimiter).concat(s[1]);
++++++++default:
++++++++++++int+l1+=+ls+/+2;
++++++++++++String[]+s1+=+Arrays.copyOfRange(s,+0,+l1);+
++++++++++++String[]+s2+=+Arrays.copyOfRange(s,+l1,+ls);+
++++++++++++return+join(delimiter,+s1).concat(delimiter).concat(join(delimiter,+s2));
++++}
}
result+=+join("",+strings);
//+Divide&Conquer+join:+7ms|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|755336|如果您别无选择，只能使用Java6或7，那么您应该使用Divide&Conquer+join。|unstyled|755337|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>String[] strings = new String[25000];
for (int i = 0; i &lt; 25000; i++) strings[i] = '1234567';

String result;
result = "";
for (String s : strings) result += s;
//linear +: 5s

result = "";
for (String s : strings) result = result.concat(s);
//linear .concat: 2.5s

result = String.join("", strings);
//Java 8 .join: 3ms

Public String join(String delimiter, String[] s)
{
 int ls = s.length;
 switch (ls)
 {
 case 0: return "";
 case 1: return s[0];
 case 2: return s[0].concat(delimiter).concat(s[1]);
 default:
 int l1 = ls / 2;
 String[] s1 = Arrays.copyOfRange(s, 0, l1); 
 String[] s2 = Arrays.copyOfRange(s, l1, ls); 
 return join(delimiter, s1).concat(delimiter).concat(join(delimiter, s2));
 }
}
result = join("", strings);
// Divide&amp;Conquer join: 7ms
</code></pre>

If you don't have the choise but to use Java 6 or 7 then you should use Divide&amp;Conquer join.

blocks|key|970934|text|从Java+8开始，我认为最简单的方法是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|970935|++++String[]+array+=+{+"cat",+"mouse"+};
++++String+delimiter+=+"";
++++String+result+=+String.join(delimiter,+array);|code-block|syntax|javascript|970936|通过这种方式，您可以选择任意分隔符。|970937|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

From Java 8, the simplest way I think is:

<pre><code> String[] array = { "cat", "mouse" };
 String delimiter = "";
 String result = String.join(delimiter, array);
</code></pre>

This way you can choose an arbitrary delimiter.

blocks|key|755393|text|String+array[]={"one","two"};
String+s="";

for(int+i=0;i<array.length;i%2B%2B)
{
++s=s%2Barray[i];
}

System.out.print(s);|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|755394|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>String array[]={"one","two"};
String s="";

for(int i=0;i&lt;array.length;i++)
{
 s=s+array[i];
}

System.out.print(s);
</code></pre>

blocks|key|755421|text|使用Apache+Commons的StringUtils+library的join方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|755422|String[]+stringArray+=+{"a","b","c"};
StringUtils.join(stringArray,+",");|code-block|syntax|javascript|755423|entityMap|0|LINK|mutability|MUTABLE|url|https://commons.apache.org/proper/commons-lang/apidocs/org/apache/commons/lang3/StringUtils.html^0|H|J|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

Use Apache Commons' <a href="https://commons.apache.org/proper/commons-lang/apidocs/org/apache/commons/lang3/StringUtils.html" rel="nofollow noreferrer">StringUtils library</a>'s join method.

<pre><code>String[] stringArray = {"a","b","c"};
StringUtils.join(stringArray, ",");
</code></pre>

I want the Java code for converting an array of strings into an string.

Convert array of strings into a string in Java

Java

我想要用于将字符串数组转换为字符串的Java代码。

问在Java中将字符串数组转换为字符串
EN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问在Java中将字符串数组转换为字符串EN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问在Java中将字符串数组转换为字符串
EN