blocks|key|867148|text|有一个非常方便的Scala对象--+scala.collection.JavaConverters|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|867149|您可以在之后执行导入和asScala操作，如下所示：|style|CODE|867150|import+scala.collection.JavaConverters._

val+lst+=+node.getByXPath(xpath).asScala
lst.foreach{+node+=>+++....+}|code-block|syntax|javascript|867151|这将为您提供Scala的Buffer表示，从而允许您完成foreach。|867152|entityMap|0|LINK|mutability|MUTABLE|url|http://www.scala-lang.org/api/current/index.html#scala.collection.JavaConverters$^0|I|V|0|0|B|7|0|0|C|6|S|7|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|6|7|10|8|@$A|11|B|12|F|G]]|9|@]|C|$]]|$1|H|3|I|5|J|7|13|8|@]|9|@]|C|$K|L]]|$1|M|3|N|5|6|7|14|8|@$A|15|B|16|F|G]|$A|17|B|18|F|G]]|9|@]|C|$]]|$1|O|3|-4|5|6|7|19|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

There's a handy Scala object just for this - <a href="http://www.scala-lang.org/api/current/index.html#scala.collection.JavaConverters$" rel="noreferrer">scala.collection.JavaConverters</a>

You can do the import and <code>asScala</code> afterwards as follows:

<pre class="lang-scala prettyprint-override"><code>import scala.collection.JavaConverters._

val lst = node.getByXPath(xpath).asScala
lst.foreach{ node =&gt; .... }
</code></pre>

This should give you Scala's <code>Buffer</code> representation allowing you to accomplish <code>foreach</code>.

blocks|key|649869|text|我正在寻找一个用Java编写的答案，但令人惊讶的是，我在这里找不到任何干净的解决方案。过了一段时间，我弄明白了，所以我决定在这里添加它，以防其他人正在寻找Java实现(我猜它在Scala中也可以工作？)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|649870|JavaConversions.asScalaBuffer(myJavaList).toList()|code-block|syntax|javascript|649871|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|$]]

I was looking for an answer written in Java and surprisingly couldn't find any clean solutions here. After a while I was able to figure it out so I decided to add it here in case someone else is looking for the Java implementation (I guess it also works in Scala?):

<pre><code>JavaConversions.asScalaBuffer(myJavaList).toList()
</code></pre>

blocks|key|649923|text|如果您必须将Java+List[ClassB]转换为Scala+List<ClassA>，则必须执行以下操作：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|649924|1)添加|649925|import+scala.collection.JavaConverters._|code-block|syntax|javascript|649926|2)使用方法asScala、toList，然后使用map|649927|List+<ClassA>+javaList+=+...
var+scalaList[ClassB]+=+javaList.asScala.toList.map(x+=>+new+ClassB(x))|649928|3)将以下内容添加到接收ClassA作为参数的ClassB构造函数中：|649929|case+class+ClassB+()+{
  +def+this+(classA:+ClassA)+{
     +this+(new+ClassB+(classA.getAttr1,+...,+classA.getAttrN))
  +}
}|649930|entityMap^0|B|C|W|C|0|0|0|6|7|E|6|P|3|0|0|C|6|N|6|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]|$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|11|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|12|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|13|8|@$9|14|A|15|B|C]|$9|16|A|17|B|C]|$9|18|A|19|B|C]]|D|@]|E|$]]|$1|O|3|P|5|J|7|1A|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|1B|8|@$9|1C|A|1D|B|C]|$9|1E|A|1F|B|C]]|D|@]|E|$]]|$1|S|3|T|5|J|7|1G|8|@]|D|@]|E|$K|L]]|$1|U|3|-4|5|6|7|1H|8|@]|D|@]|E|$]]]|V|$]]

If you have to convert a Java <code>List&lt;ClassA&gt;</code> to a Scala <code>List[ClassB]</code>, then you must do the following:

1) Add

<pre><code>import scala.collection.JavaConverters._
</code></pre>

2) Use methods <code>asScala</code>, <code>toList</code> and then <code>map</code>

<pre><code>List &lt;ClassA&gt; javaList = ...
var scalaList[ClassB] = javaList.asScala.toList.map(x =&gt; new ClassB(x))
</code></pre>

3) Add the following to the <code>ClassB</code> constructor that receives <code>ClassA</code> as a parameter:

<pre><code>case class ClassB () {
   def this (classA: ClassA) {
      this (new ClassB (classA.getAttr1, ..., classA.getAttrN))
   }
}
</code></pre>

blocks|key|867345|text|从Scala2.8.1开始，使用asScala和asJava方法使用JavaConverters._来转换scala和Java集合。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|867346|import+scala.collection.JavaConverters._|867347|javalist.asScala|867348|scalaSeq.asJava|867349|请参阅转换关系scala+doc+site|867350|entityMap|0|LINK|mutability|MUTABLE|url|http://www.scala-lang.org/api/2.9.3/scala/collection/JavaConverters$.html^0|Y|G|0|0|14|0|0|G|0|0|F|0|7|E|0|0^^$0|@$1|2|3|4|5|6|7|V|8|@$9|W|A|X|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|11|8|@$9|12|A|13|B|C]]|D|@]|E|$]]|$1|J|3|K|5|6|7|14|8|@$9|15|A|16|B|C]]|D|@]|E|$]]|$1|L|3|M|5|6|7|17|8|@]|D|@$9|18|A|19|1|1A]]|E|$]]|$1|N|3|-4|5|6|7|1B|8|@]|D|@]|E|$]]]|O|$P|$5|Q|R|S|E|$T|U]]]]

Since scala 2.8.1 use <code>JavaConverters._</code>
to convert scala and Java collections using asScala and asJava methods.

<code>import scala.collection.JavaConverters._</code>

<code>javalist.asScala</code>

<code>scalaSeq.asJava</code> 

see the Conversion relationship <a href="http://www.scala-lang.org/api/2.9.3/scala/collection/JavaConverters$.html" rel="nofollow noreferrer">scala doc site</a>

blocks|key|867388|text|将java列表转换为scala列表的快捷方式|type|unstyled|depth|inlineStyleRanges|entityRanges|data|867389|import+scala.jdk.CollectionConverters._|offset|length|style|CODE|867390|myjavaList.asScala.toList|867391|entityMap^0|0|0|13|0|0|P|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@$D|N|E|O|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|P|8|@$D|Q|E|R|F|G]]|9|@]|A|$]]|$1|J|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|K|$]]

Shortcut to convert java list to scala list
<code>import scala.jdk.CollectionConverters._</code>
<code>myjavaList.asScala.toList</code>

I have a Java API that returns a List like:

<pre><code>public List&lt;?&gt; getByXPath(String xpathExpr)
</code></pre>

I am using the below scala code:

<pre><code>val lst = node.getByXPath(xpath)
</code></pre>

Now if I try scala syntax sugar like:

<pre><code>lst.foreach{ node =&gt; ... }
</code></pre>

it does not work. I get the error:

<pre><code>value foreach is not a member of java.util.List[?0]
</code></pre>

It seems I need to convert Java List to Scala List. How to do that in above context?

How to get Scala List from Java List?

Java

我有一个Java API，它返回如下列表：public List<?> getByXPath(String xpathExpr)我使用下面的scala代码：val lst = node.getByXPath(xpath)现在，如果我尝试scala语法，如下所示：lst.foreach{ node => ... }它不起...

问如何从Java列表中获取Scala列表？
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