entityMap|blocks|key|dou39|text|简明扼要的一句话：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|8cjp2|import+java.io.PrintWriter
new+PrintWriter("filename")+{+write("file+contents");+close+}|code-block|syntax|javascript^0|0^^$0|$]|1|@$2|3|4|5|6|7|8|H|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|I|9|@]|A|@]|B|$F|G]]]]

A concise one line:

<pre><code>import java.io.PrintWriter
new PrintWriter("filename") { write("file contents"); close }
</code></pre>

entityMap|blocks|key|l2u3|text|奇怪的是，没有人建议NIO.2操作(从Java+7开始提供)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|9slt5|import+java.nio.file.{Paths,+Files}
import+java.nio.charset.StandardCharsets

Files.write(Paths.get("file.txt"),+"file+contents".getBytes(StandardCharsets.UTF_8))|code-block|syntax|javascript|3fhai|我认为这是到目前为止最简单、最容易、最地道的方法，而且它不需要Java本身的任何依赖。^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|J|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|K|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|L|9|@]|A|@]|B|$]]]]

It is strange that no one had suggested NIO.2 operations (available since Java 7):

<pre><code>import java.nio.file.{Paths, Files}
import java.nio.charset.StandardCharsets

Files.write(Paths.get("file.txt"), "file contents".getBytes(StandardCharsets.UTF_8))
</code></pre>

I think this is by far the simplest and easiest and most idiomatic way, and it does not need any dependencies sans Java itself.

entityMap|blocks|key|b9tfp|text|下面是一个使用reflect.io.file的简洁的一行代码，它适用于Scala2.12：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|cnpb8|reflect.io.File("filename").writeAll("hello+world")|code-block|syntax|javascript|c4q2v|或者，如果你想使用Java库，你可以这样做：|3g7v2|Some(new+PrintWriter("filename")).foreach{p+=>+p.write("hello+world");+p.close}^0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|L|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|M|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|N|9|@]|A|@]|B|$]]|$2|J|4|K|6|E|8|O|9|@]|A|@]|B|$F|G]]]]

Here is a concise one-liner using reflect.io.file, this works with Scala 2.12:

<pre><code>reflect.io.File("filename").writeAll("hello world")
</code></pre>

Alternatively, if you want to use the Java libraries you can do this hack:

<pre><code>Some(new PrintWriter("filename")).foreach{p =&gt; p.write("hello world"); p.close}
</code></pre>

entityMap|blocks|key|6k23k|text|如果您喜欢Groovy语法，可以使用皮条客-我的图书馆|type|unstyled|depth|inlineStyleRanges|entityRanges|data|173a5|将其引入Scala的设计模式：|d9uco|import+java.io._
import+scala.io._

class+RichFile(+file:+File+)+{

++def+text+=+Source.fromFile(+file+)(Codec.UTF8).mkString

++def+text_=(+s:+String+)+{
++++val+out+=+new+PrintWriter(+file+,+"UTF-8")
++++try{+out.print(+s+)+}
++++finally{+out.close+}
++}
}

object+RichFile+{

++implicit+def+enrichFile(+file:+File+)+=+new+RichFile(+file+)

}|code-block|syntax|javascript|1rbpc|它将按预期工作：|3uaku|scala>+import+RichFile.enrichFile
import+RichFile.enrichFile

scala>+val+f+=+new+File("/tmp/example.txt")
f:+java.io.File+=+/tmp/example.txt

scala>+f.text+=+"hello+world"

scala>+f.text
res1:+String+=+
"hello+world^0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|N|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|O|9|@]|A|@]|B|$]]|$2|E|4|F|6|G|8|P|9|@]|A|@]|B|$H|I]]|$2|J|4|K|6|7|8|Q|9|@]|A|@]|B|$]]|$2|L|4|M|6|G|8|R|9|@]|A|@]|B|$H|I]]]]

If you like Groovy syntax, you can use the Pimp-My-Library design pattern to bring it to Scala:

<pre><code>import java.io._
import scala.io._

class RichFile( file: File ) {

 def text = Source.fromFile( file )(Codec.UTF8).mkString

 def text_=( s: String ) {
 val out = new PrintWriter( file , "UTF-8")
 try{ out.print( s ) }
 finally{ out.close }
 }
}

object RichFile {

 implicit def enrichFile( file: File ) = new RichFile( file )

}
</code></pre>

It will work as expected:

<pre><code>scala&gt; import RichFile.enrichFile
import RichFile.enrichFile

scala&gt; val f = new File("/tmp/example.txt")
f: java.io.File = /tmp/example.txt

scala&gt; f.text = "hello world"

scala&gt; f.text
res1: String = 
"hello world
</code></pre>

entityMap|blocks|key|9n8d3|text|import+sys.process._
"echo+hello+world"+#>+new+java.io.File("/tmp/example.txt")+!|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript^0^^$0|$]|1|@$2|3|4|5|6|7|8|E|9|@]|A|@]|B|$C|D]]]]

<pre><code>import sys.process._
"echo hello world" #&gt; new java.io.File("/tmp/example.txt") !
</code></pre>

entityMap|blocks|key|6u424|text|我写的一个微库：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|c1j7g|https://github.com/pathikrit/better-files|4usqc|file.write("Hi!")|code-block|syntax|javascript|3u039|或者|prj2|file+<<+"Hi!"^0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|N|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|O|9|@]|A|@]|B|$]]|$2|E|4|F|6|G|8|P|9|@]|A|@]|B|$H|I]]|$2|J|4|K|6|7|8|Q|9|@]|A|@]|B|$]]|$2|L|4|M|6|G|8|R|9|@]|A|@]|B|$H|I]]]]

A micro library I wrote: <a href="https://github.com/pathikrit/better-files" rel="noreferrer">https://github.com/pathikrit/better-files</a>

<pre><code>file.write("Hi!")
</code></pre>

or

<pre><code>file &lt;&lt; "Hi!"
</code></pre>

entityMap|blocks|key|2kq9o|text|您可以轻松地使用Apache文件实用程序。查看函数writeStringToFile我们在我们的项目中使用这个库。|type|unstyled|depth|inlineStyleRanges|entityRanges|data^0^^$0|$]|1|@$2|3|4|5|6|7|8|C|9|@]|A|@]|B|$]]]]

You can easily use <a href="http://commons.apache.org/io/apidocs/org/apache/commons/io/FileUtils.html">Apache File Utils</a>. Look at function <code>writeStringToFile</code>. We use this library in our projects.

entityMap|blocks|key|amjro|text|其中一个也有这样的格式，它既简洁又底层的库写得很漂亮(参见源代码)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|48t06|import+scalax.io.Codec
import+scalax.io.JavaConverters._

implicit+val+codec+=+Codec.UTF8

new+java.io.File("hi-file.txt").asOutput.write("I'm+a+hi+file!+...+Really!")|code-block|syntax|javascript^0|0^^$0|$]|1|@$2|3|4|5|6|7|8|H|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|I|9|@]|A|@]|B|$F|G]]]]

One also has this format, which is both concise and the underlying library is beautifully written (see the source code):

<pre><code>import scalax.io.Codec
import scalax.io.JavaConverters._

implicit val codec = Codec.UTF8

new java.io.File("hi-file.txt").asOutput.write("I'm a hi file! ... Really!")
</code></pre>

entityMap|blocks|key|3m5v7|text|我想这已经足够简洁了：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|9gq3v|scala>+import+java.io._
import+java.io._

scala>+val+w+=+new+BufferedWriter(new+FileWriter("output.txt"))
w:+java.io.BufferedWriter+=+java.io.BufferedWriter@44ba4f

scala>+w.write("Alice\r\nBob\r\nCharlie\r\n")

scala>+w.close()|code-block|syntax|javascript^0|0^^$0|$]|1|@$2|3|4|5|6|7|8|H|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|I|9|@]|A|@]|B|$F|G]]]]

This is concise enough, I guess:

<pre><code>scala&gt; import java.io._
import java.io._

scala&gt; val w = new BufferedWriter(new FileWriter("output.txt"))
w: java.io.BufferedWriter = java.io.BufferedWriter@44ba4f

scala&gt; w.write("Alice\r\nBob\r\nCharlie\r\n")

scala&gt; w.close()
</code></pre>

entityMap|blocks|key|bao61|text|您可以通过混合使用Java和Scala库来实现这一点。您将完全控制字符编码。但不幸的是，文件句柄不会正确关闭。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|e908p|scala>+import+java.io.ByteArrayInputStream
import+java.io.ByteArrayInputStream

scala>+import+java.io.FileOutputStream
import+java.io.FileOutputStream

scala>+BasicIO.transferFully(new+ByteArrayInputStream("test".getBytes("UTF-8")),+new+FileOutputStream("test.txt"))|code-block|syntax|javascript^0|0^^$0|$]|1|@$2|3|4|5|6|7|8|H|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|I|9|@]|A|@]|B|$F|G]]]]

You can do this with a mix of Java and Scala libraries. You will have full control over the character encoding. But unfortunately, the file handles will not be closed properly. 

<pre><code>scala&gt; import java.io.ByteArrayInputStream
import java.io.ByteArrayInputStream

scala&gt; import java.io.FileOutputStream
import java.io.FileOutputStream

scala&gt; BasicIO.transferFully(new ByteArrayInputStream("test".getBytes("UTF-8")), new FileOutputStream("test.txt"))
</code></pre>

entityMap|blocks|key|5gcqt|text|更新:我已经创建了一个更有效的解决方案，我在这里进行了详细说明：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|cv9jt|https://stackoverflow.com/a/34277491/501113|4nrt|我发现自己越来越多地在Scala+IDE+for+Eclipse中使用Scala工作表(我相信在IntelliJ+IDEA中也有类似的东西)。无论如何，当我得到“输出超过截止限制”时，我需要能够执行一行程序来输出一些内容。如果我正在做任何重要的事情，特别是使用Scala集合时，我会收到一条消息。|42tq6|我想出了一个插入到每个新Scala工作表顶部的一行代码来简化这一过程(这样我就不必为了一个非常简单的需求而执行整个外部库导入操作)。如果你是一个固执己见的人，注意到从技术上讲，它只有两行，这只是为了让它在这个论坛上更具可读性。它是我的Scala工作表中的一行。|9eplu|def+printToFile(content:+String,+location:+String+=+"C:/Users/jtdoe/Desktop/WorkSheet.txt")+=
++Some(new+java.io.PrintWriter(location)).foreach{f+=>+try{f.write(content)}finally{f.close}}|code-block|syntax|javascript|b911g|用法很简单：|3rat1|printToFile("A+fancy+test+string\ncontaining+newlines\nOMG!\n")|dqcn8|这允许我有选择地提供文件名，如果我想要有超过缺省值的其他文件(这将在每次调用该方法时完全覆盖该文件)。|7ao7d|因此，第二种用法很简单：|762gc|printToFile("A+fancy+test+string\ncontaining+newlines\nOMG!\n",+"C:/Users/jtdoe/Desktop/WorkSheet.txt")|3pkcp|尽情享受吧！^0|0|0|0|0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|Z|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|10|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|11|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|12|9|@]|A|@]|B|$]]|$2|I|4|J|6|K|8|13|9|@]|A|@]|B|$L|M]]|$2|N|4|O|6|7|8|14|9|@]|A|@]|B|$]]|$2|P|4|Q|6|K|8|15|9|@]|A|@]|B|$L|M]]|$2|R|4|S|6|7|8|16|9|@]|A|@]|B|$]]|$2|T|4|U|6|7|8|17|9|@]|A|@]|B|$]]|$2|V|4|W|6|K|8|18|9|@]|A|@]|B|$L|M]]|$2|X|4|Y|6|7|8|19|9|@]|A|@]|B|$]]]]

UPDATE: I have since created a more effective solution upon which I have elaborated here: <a href="https://stackoverflow.com/a/34277491/501113">https://stackoverflow.com/a/34277491/501113</a>

I find myself working more and more in the Scala Worksheet within the Scala IDE for Eclipse (and I believe there is something equivalent in IntelliJ IDEA). Anyway, I need to be able to do a one-liner to output some of the contents as I get the "Output exceeds cutoff limit." message if I am doing anything significant, especially with the Scala collections.

I came up with a one-liner I insert into the top of each new Scala Worksheet to simplify this (and so I don't have to do the whole external library import exercise for a very simple need). If you are a stickler and notice that it is technically two lines, it's only to make it more readable in this forum. It is a single line in my Scala Worksheet.

<pre><code>def printToFile(content: String, location: String = "C:/Users/jtdoe/Desktop/WorkSheet.txt") =
 Some(new java.io.PrintWriter(location)).foreach{f =&gt; try{f.write(content)}finally{f.close}}
</code></pre>

And the usage is simply: 

<pre><code>printToFile("A fancy test string\ncontaining newlines\nOMG!\n")
</code></pre>

This allows me to optionally provide the file name should I want to have additional files beyond the default (which completely overwrites the file each time the method is called).

So, the second usage is simply: 

<pre><code>printToFile("A fancy test string\ncontaining newlines\nOMG!\n", "C:/Users/jtdoe/Desktop/WorkSheet.txt")
</code></pre>

Enjoy!

entityMap|blocks|key|2ke9i|text|我知道这不是一句话，但据我所知，它解决了安全问题；|type|unstyled|depth|inlineStyleRanges|entityRanges|data|feckc|//+This+possibly+creates+a+FileWriter,+but+maybe+not
val+writer+=+Try(new+FileWriter(new+File("filename")))
//+If+it+did,+we+use+it+to+write+the+data+and+return+it+again
//+If+it+didn't+we+skip+the+map+and+print+the+exception+and+return+the+original,+just+in-case+it+was+actually+.write()+that+failed
//+Then+we+close+the+file
writer.map(w+=>+{w.write("data");+w}).recoverWith{case+e+=>+{e.printStackTrace();+writer}}.map(_.close)|code-block|syntax|javascript|b3p0r|如果您不关心异常处理，那么您可以编写|b5odh|writer.map(w+=>+{w.writer("data");+w}).recoverWith{case+_+=>+writer}.map(_.close)^0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|L|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|M|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|N|9|@]|A|@]|B|$]]|$2|J|4|K|6|E|8|O|9|@]|A|@]|B|$F|G]]]]

I know it's not one line, but it solves the safety issues as far as I can tell;

<pre><code>// This possibly creates a FileWriter, but maybe not
val writer = Try(new FileWriter(new File("filename")))
// If it did, we use it to write the data and return it again
// If it didn't we skip the map and print the exception and return the original, just in-case it was actually .write() that failed
// Then we close the file
writer.map(w =&gt; {w.write("data"); w}).recoverWith{case e =&gt; {e.printStackTrace(); writer}}.map(_.close)
</code></pre>

If you didn't care about the exception handling then you can write

<pre><code>writer.map(w =&gt; {w.writer("data"); w}).recoverWith{case _ =&gt; writer}.map(_.close)
</code></pre>

entityMap|blocks|key|b0c6g|text|使用菊石ops库。语法非常简单，但是库的广度几乎和人们在像bash这样的shell脚本语言中尝试这样的任务时所期望的一样宽。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4l0qg|在我链接的页面上，它显示了可以对库执行的许多操作，但为了回答这个问题，这是一个写入文件的示例|12ko0|import+ammonite.ops._
write(pwd/'"file.txt",+"file+contents")|code-block|syntax|javascript^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|J|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|K|9|@]|A|@]|B|$]]|$2|E|4|F|6|G|8|L|9|@]|A|@]|B|$H|I]]]]

Use <a href="https://ammonite.io/#Ammonite-Ops" rel="nofollow noreferrer">ammonite ops</a> library. The syntax is very minimal, but the breadth of the library is almost as wide as what one would expect from attempting such a task in a shell scripting language like bash.
On the page I linked to, it shows numerous operations one can do with the library, but to answer this question, this is an example of writing to a file
<pre><code>import ammonite.ops._
write(pwd/'&quot;file.txt&quot;, &quot;file contents&quot;)
</code></pre>

entityMap|blocks|key|fvsel|text|这是一个现代的，安全的线条：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|774me|java.nio.file.Files.write(java.nio.file.Paths.get("/tmp/output.txt"),+"Hello+world".getBytes());|code-block|syntax|javascript|1mufk|nio是默认情况下随JDK一起提供的现代IO库，因此不需要导入或依赖项。^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|J|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|K|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|L|9|@]|A|@]|B|$]]]]

Here's the modern, safe one liner:
<pre><code>java.nio.file.Files.write(java.nio.file.Paths.get(&quot;/tmp/output.txt&quot;), &quot;Hello world&quot;.getBytes());
</code></pre>
nio is a modern IO library shipped by default with the JDK 9+ so no imports or dependencies required.

entityMap|blocks|key|63e9o|text|os-lib是写入文件的最好的现代方式，正如这里提到的下面是如何将"hello“写给file.txt文件。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2s30n|os.write(os.pwd/"file.txt",+"hello")|code-block|syntax|javascript|dd5of|os-lib隐藏了Java的丑陋和复杂性(它在幕后使用Java库，所以它的性能一样好)。请参见这里有关使用lib的更多信息。^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|J|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|K|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|L|9|@]|A|@]|B|$]]]]

<a href="https://github.com/lihaoyi/os-lib" rel="nofollow noreferrer">os-lib</a> is the best modern way to write to a file, <a href="https://stackoverflow.com/questions/4604237/how-to-write-to-a-file-in-scala/56310893#56310893">as mentioned here</a>.
Here's how to write &quot;hello&quot; to the <code>file.txt</code> file.
<pre><code>os.write(os.pwd/&quot;file.txt&quot;, &quot;hello&quot;)
</code></pre>
os-lib hides the Java ugliness and complexity (it uses the Java libs under the hood, so it's just as performant). See <a href="https://mungingdata.com/scala/filesystem-paths-move-copy-list-delete-folders/" rel="nofollow noreferrer">here</a> for more info about using the lib.

entityMap|blocks|key|8vilj|text|通过分号的魔力，你可以把你喜欢的任何东西变成一行。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|12ndj|import+java.io.PrintWriter
import+java.nio.file.Files
import+java.nio.file.Paths
import+java.nio.charset.StandardCharsets
import+java.nio.file.StandardOpenOption
val+outfile+=+java.io.File.createTempFile("",+"").getPath
val+outstream+=+new+PrintWriter(Files.newBufferedWriter(Paths.get(outfile)
++,+StandardCharsets.UTF_8
++,+StandardOpenOption.WRITE));+outstream.println("content");+outstream.flush();+outstream.close()|code-block|syntax|javascript^0|0^^$0|$]|1|@$2|3|4|5|6|7|8|H|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|I|9|@]|A|@]|B|$F|G]]]]

Through the magic of the semicolon, you can make anything you like a one-liner.

<pre><code>import java.io.PrintWriter
import java.nio.file.Files
import java.nio.file.Paths
import java.nio.charset.StandardCharsets
import java.nio.file.StandardOpenOption
val outfile = java.io.File.createTempFile("", "").getPath
val outstream = new PrintWriter(Files.newBufferedWriter(Paths.get(outfile)
 , StandardCharsets.UTF_8
 , StandardOpenOption.WRITE)); outstream.println("content"); outstream.flush(); outstream.close()
</code></pre>

For reading files in Scala, there is 

<pre><code>Source.fromFile("file.txt").mkString
</code></pre>

Is there an equivalent and concise way to write a string to file?

Most languages support something like that. My favorite is Groovy:

<pre><code>def f = new File("file.txt")
// Read
def s = f.text
// Write
f.text = "file contents"
</code></pre>

I'd like to use the code for programs ranging from a single line to a short page of code. Having to use your own library doesn't make sense here. I expect a modern language to let me write something to a file conveniently. 

There are posts similar to this, but they don't answer my exact question or are focused on older Scala versions.

For example:

<ul>
<li><a href="https://stackoverflow.com/questions/1284423/read-entire-file-in-scala">Read entire file in Scala?</a></li>
<li><a href="https://stackoverflow.com/questions/4604237/how-to-write-to-a-file-in-scala">How to write to a file in Scala?</a></li>
</ul>

Scala: write string to file in one statement

IntelliJ IDEA

Eclipse

Java

 要在Scala中读取文件，有 Source.fromFile("file.txt").mkString 有没有一种等价而简洁的方法将字符串写到文件中？ 大多数语言都支持这样的东西。我最喜欢的是Groovy： def f = new File("file.txt")// Readdef s = f.text// Writef.text = "file contents" 我想在程序中使用代码，范围

问Scala:在一条语句中将字符串写入文件
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