blocks|key|886837|text|在写入之前，您需要确保父目录已经存在。你可以通过File#mkdirs()来做这件事。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|886838|File+f+=+new+File("C:/a/b/test.txt");
f.getParentFile().mkdirs();
//+...|code-block|syntax|javascript|886839|entityMap|0|LINK|mutability|MUTABLE|url|http://download.oracle.com/javase/6/docs/api/java/io/File.html#mkdirs%2528%2529^0|O|D|O|D|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@$9|V|A|W|1|X]]|E|$]]|$1|F|3|G|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

You need to ensure that the parent directories exist before writing. You can do this by <a href="http://download.oracle.com/javase/6/docs/api/java/io/File.html#mkdirs%28%29" rel="noreferrer"><code>File#mkdirs()</code></a>.

<pre><code>File f = new File("C:/a/b/test.txt");
f.getParentFile().mkdirs();
// ...
</code></pre>

blocks|key|669728|text|使用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|669729|File+f+=+new+File("C:\\a\\b\\test.txt");
f.mkdirs();
f.createNewFile();|code-block|syntax|javascript|669730|请注意，我将Windows文件系统中路径的正斜杠更改为双反斜杠。这将在给定的路径上创建一个空文件。|669731|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|$]]

Use:

<pre><code>File f = new File("C:\\a\\b\\test.txt");
f.mkdirs();
f.createNewFile();
</code></pre>

Notice I changed the forward slashes to double back slashes for paths in Windows File System. This will create an empty file on the given path.

blocks|key|669748|text|最好的方法是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|669749|String+path+=+"C:"+%2B+File.separator+%2B+"hello"+%2B+File.separator+%2B+"hi.txt";
//+Use+relative+path+for+Unix+systems
File+f+=+new+File(path);

f.getParentFile().mkdirs();+
f.createNewFile();|code-block|syntax|javascript|669750|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|$]]

The best way to do it is:

<pre><code>String path = "C:" + File.separator + "hello" + File.separator + "hi.txt";
// Use relative path for Unix systems
File f = new File(path);

f.getParentFile().mkdirs(); 
f.createNewFile();
</code></pre>

blocks|key|669762|text|String+path+=+"C:"%2BFile.separator%2B"hello";
String+fname=+path%2BFile.separator%2B"abc.txt";
++++File+f+=+new+File(path);
++++File+f1+=+new+File(fname);

++++f.mkdirs()+;
++++try+{
++++++++f1.createNewFile();
++++}+catch+(IOException+e)+{
++++++++//+TODO+Auto-generated+catch+block
++++++++e.printStackTrace();
++++}
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|669763|这应该会在目录中创建一个新文件|unstyled|669764|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 path = "C:"+File.separator+"hello";
String fname= path+File.separator+"abc.txt";
 File f = new File(path);
 File f1 = new File(fname);

 f.mkdirs() ;
 try {
 f1.createNewFile();
 } catch (IOException e) {
 // TODO Auto-generated catch block
 e.printStackTrace();
 }
}
</code></pre>

This should create a new file inside a directory

blocks|key|886998|text|通过Java+7，您可以使用Path、Paths和Files|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|886999|import+java.io.IOException;
import+java.nio.file.FileAlreadyExistsException;
import+java.nio.file.Files;
import+java.nio.file.Path;
import+java.nio.file.Paths;

public+class+CreateFile+{

++++public+static+void+main(String[]+args)+throws+IOException+{
++++++++Path+path+=+Paths.get("/tmp/foo/bar.txt");

++++++++Files.createDirectories(path.getParent());

++++++++try+{
++++++++++++Files.createFile(path);
++++++++}+catch+(FileAlreadyExistsException+e)+{
++++++++++++System.err.println("already+exists:+"+%2B+e.getMessage());
++++++++}
++++}
}|code-block|syntax|javascript|887000|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/7/docs/api/java/nio/file/package-summary.html|1|http://docs.oracle.com/javase/7/docs/api/java/nio/file/Path.html|2|http://docs.oracle.com/javase/7/docs/api/java/nio/file/Paths.html|3|http://docs.oracle.com/javase/7/docs/api/java/nio/file/Files.html^0|E|4|J|5|P|5|2|6|0|E|4|1|J|5|2|P|5|3|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$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]|$9|18|A|19|1|1A]|$9|1B|A|1C|1|1D]|$9|1E|A|1F|1|1G]]|E|$]]|$1|F|3|G|5|H|7|1H|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|1I|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]|S|$5|N|O|P|E|$Q|T]]|U|$5|N|O|P|E|$Q|V]]|W|$5|N|O|P|E|$Q|X]]]]

With <a href="http://docs.oracle.com/javase/7/docs/api/java/nio/file/package-summary.html">Java 7</a>, you can use <a href="http://docs.oracle.com/javase/7/docs/api/java/nio/file/Path.html"><code>Path</code></a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/nio/file/Paths.html"><code>Paths</code></a>, and <a href="http://docs.oracle.com/javase/7/docs/api/java/nio/file/Files.html"><code>Files</code></a>:

<pre><code>import java.io.IOException;
import java.nio.file.FileAlreadyExistsException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class CreateFile {

 public static void main(String[] args) throws IOException {
 Path path = Paths.get("/tmp/foo/bar.txt");

 Files.createDirectories(path.getParent());

 try {
 Files.createFile(path);
 } catch (FileAlreadyExistsException e) {
 System.err.println("already exists: " + e.getMessage());
 }
 }
}
</code></pre>

blocks|key|887017|text|一种更好、更简单的方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|887018|File+f+=+new+File("C:/a/b/test.txt");
if(!f.exists()){
+++f.createNewFile();
}|code-block|syntax|javascript|887019|Source|offset|length|887020|entityMap|0|LINK|mutability|MUTABLE|url|http://tutoref.com/how-to-create-directories-in-java/^0|0|0|0|6|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

A better and simpler way to do that :

<pre><code>File f = new File("C:/a/b/test.txt");
if(!f.exists()){
 f.createNewFile();
}
</code></pre>

<a href="http://tutoref.com/how-to-create-directories-in-java/" rel="nofollow noreferrer">Source</a>

blocks|key|669872|text|令人惊讶的是，许多答案都没有给出完整的工作代码。这就是它：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|669873|public+static+void+createFile(String+fullPath)+throws+IOException+{
++++File+file+=+new+File(fullPath);
++++file.getParentFile().mkdirs();
++++file.createNewFile();
}

public+static+void+main(String+[]+args)+throws+Exception+{
++++String+path+=+"C:/donkey/bray.txt";
++++createFile(path);
}|code-block|syntax|javascript|669874|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|$]]

Surprisingly, many of the answers don't give complete working code. Here it is:

<pre><code>public static void createFile(String fullPath) throws IOException {
 File file = new File(fullPath);
 file.getParentFile().mkdirs();
 file.createNewFile();
}

public static void main(String [] args) throws Exception {
 String path = "C:/donkey/bray.txt";
 createFile(path);
}
</code></pre>

blocks|key|887075|text|要创建一个文件并在其中写入一些字符串：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|887076|BufferedWriter+bufferedWriter+=+Files.newBufferedWriter(Paths.get("Path+to+your+file"));
bufferedWriter.write("Some+string");+//+to+write+some+data
//+bufferedWriter.write("");+++++++++//+for+empty+file
bufferedWriter.close();|code-block|syntax|javascript|887077|这适用于Mac和PC。|887078|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|$]]

To create a file and write some string there:

<pre><code>BufferedWriter bufferedWriter = Files.newBufferedWriter(Paths.get("Path to your file"));
bufferedWriter.write("Some string"); // to write some data
// bufferedWriter.write(""); // for empty file
bufferedWriter.close();
</code></pre>

This works for Mac and PC.

blocks|key|669944|text|要使用FileOutputStream，请尝试以下命令：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|669945|public+class+Main01{
++++public+static+void+main(String[]+args)+throws+FileNotFoundException{
++++++++FileOutputStream+f+=+new+FileOutputStream("file.txt");
++++++++PrintStream+p+=+new+PrintStream(f);
++++++++p.println("George.........");
++++++++p.println("Alain..........");
++++++++p.println("Gerard.........");
++++++++p.close();
++++++++f.close();
++++}
}|code-block|syntax|javascript|669946|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|$]]

For using the FileOutputStream try this : 

<pre><code>public class Main01{
 public static void main(String[] args) throws FileNotFoundException{
 FileOutputStream f = new FileOutputStream("file.txt");
 PrintStream p = new PrintStream(f);
 p.println("George.........");
 p.println("Alain..........");
 p.println("Gerard.........");
 p.close();
 f.close();
 }
}
</code></pre>

blocks|key|887124|text|当您通过文件输出流写入文件时，将自动创建文件。但要确保创建了所有必要的目录(文件夹)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|887125|++++String+absolutePath+=+...
++++try{
+++++++File+file+=+new+File(absolutePath);
+++++++file.mkdirs()+;
+++++++//all+parent+folders+are+created
+++++++//now+the+file+will+be+created+when+you+start+writing+to+it+via+FileOutputStream.
++++++}catch+(Exception+e){
++++++++System.out.println("Error+:+"%2B+e.getmessage());
+++++++}|code-block|syntax|javascript|887126|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|$]]

When you write to the file via file output stream, the file will be created automatically. but make sure all necessary directories ( folders) are created.
<pre><code> String absolutePath = ...
 try{
 File file = new File(absolutePath);
 file.mkdirs() ;
 //all parent folders are created
 //now the file will be created when you start writing to it via FileOutputStream.
 }catch (Exception e){
 System.out.println(&quot;Error : &quot;+ e.getmessage());
 }
</code></pre>

If I want to create a file in <code>C:/a/b/test.txt</code>, can I do something like:

<pre><code>File f = new File("C:/a/b/test.txt");
</code></pre>

Also, I want to use <code>FileOutputStream</code> to create the file. So how would I do it? For some reason the file doesn't get created in the right directory.

How to create a file in a directory in java?

文件系统

Windows

Unix

如果我想在C:/a/b/test.txt中创建一个文件，我可以这样做吗：File f = new File("C:/a/b/test.txt");另外，我想使用FileOutputStream来创建文件。那么我该怎么做呢？由于某些原因，文件没有在正确的目录中创建。

问如何在java的目录中创建文件？
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问如何在java的目录中创建文件？
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