问题

用java怎么创建一个文件并向该文件写文本内容

最佳答案:

创建一个文本文件（注意：如果该文件存在，则会覆盖该文件）

PrintWriter writer = new PrintWriter("the-file-name.txt", "UTF-8");
writer.println("The first line");
writer.println("The second line");
writer.close();

创建一个二进制文件（同样会覆盖这文件）

byte data[] = ...
FileOutputStream out = new FileOutputStream("the-file-name");
out.write(data);
out.close();

Java 7+ 用户可以用File类来写文件
创建一个文本文件

List<String> lines = Arrays.asList("The first line", "The second line");
Path file = Paths.get("the-file-name.txt");
Files.write(file, lines, Charset.forName("UTF-8"));
//Files.write(file, lines, Charset.forName("UTF-8"), StandardOpenOption.APPEND);

创建一个二进制文件

byte data[] = ...
Path file = Paths.get("the-file-name");
Files.write(file, data);
//Files.write(file, data, StandardOpenOption.APPEND);

其他的答案（1）:

在Java 7+中

try (Writer writer = new BufferedWriter(new OutputStreamWriter(
              new FileOutputStream("filename.txt"), "utf-8"))) {
   writer.write("something");
}

还有一些实用的方法如下：

• FileUtils.writeStringtoFile(..) 来自于 commons-io 包
• Files.write(..) 来自于 guava

Note also that you can use a FileWriter, but it uses the default encoding,
which is often a bad idea - it’s best to specify the encoding explicitly.
还要注意可以使用 FileWriter，但是它使用的是默认编码，这不是很好的方法，最好是明确指定编码

下面是来自于prior-to-java-7的原始方法

Writer writer = null;

try {
    writer = new BufferedWriter(new OutputStreamWriter(
          new FileOutputStream("filename.txt"), "utf-8"));
    writer.write("Something");
} catch (IOException ex) {
  // report
} finally {
   try {writer.close();} catch (Exception ex) {/*ignore*/}
}

可以看Reading, Writing, and Creating Files(包含NIO2)

其他答案（2）：

public class Program {
    public static void main(String[] args) {
        String text = "Hello world";
        BufferedWriter output = null;
        try {
            File file = new File("example.txt");
            output = new BufferedWriter(new FileWriter(file));
            output.write(text);
        } catch ( IOException e ) {
            e.printStackTrace();
        } finally {
            if ( output != null ) output.close();
        }
    }
}

其他答案（3）：

如果已经有想要写到文件中的内容，java.nio.file.Files 作为 Java 7 附加部分的native I/O，提供了简单高效的方法来实现你的目标

基本上创建文件，写文件只需要一行，而且是只需一个方法调用！
下面的例子创建并且写了6个不同的文件来展示是怎么使用的

Charset utf8 = StandardCharsets.UTF_8;
List<String> lines = Arrays.asList("1st line", "2nd line");
byte[] data = {1, 2, 3, 4, 5};

try {
    Files.write(Paths.get("file1.bin"), data);
    Files.write(Paths.get("file2.bin"), data,
            StandardOpenOption.CREATE, StandardOpenOption.APPEND);
    Files.write(Paths.get("file3.txt"), "content".getBytes());
    Files.write(Paths.get("file4.txt"), "content".getBytes(utf8));
    Files.write(Paths.get("file5.txt"), lines, utf8);
    Files.write(Paths.get("file6.txt"), lines, utf8,
            StandardOpenOption.CREATE, StandardOpenOption.APPEND);
} catch (IOException e) {
    e.printStackTrace();
}

其他答案（4）：

下面是一个小程序来创建和写文件。该版本的代码比较长，但是可以容易理解

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;

public class writer {
    public void writing() {
        try {
            //Whatever the file path is.
            File statText = new File("E:/Java/Reference/bin/images/statsTest.txt");
            FileOutputStream is = new FileOutputStream(statText);
            OutputStreamWriter osw = new OutputStreamWriter(is);    
            Writer w = new BufferedWriter(osw);
            w.write("POTATO!!!");
            w.close();
        } catch (IOException e) {
            System.err.println("Problem writing to the file statsTest.txt");
        }
    }

    public static void main(String[]args) {
        writer write = new writer();
        write.writing();
    }
}

stackoverflow链接：
http://stackoverflow.com/questions/2885173/how-to-create-a-file-and-write-to-a-file-in-java