使用Apache Commons IO api。它很简单

使用API作为

 FileUtils.writeStringToFile(new File("FileNameToWrite.txt"), "stringToWrite");

Maven依赖项

<dependency>
    <groupId>commons-io</groupId>
    <artifactId>commons-io</artifactId>
    <version>2.4</version>
</dependency>

最好在finally块中关闭writer/outputstream，以防发生意外

finally{
   if(writer != null){
     try{
        writer.flush();
        writer.close();
     }
     catch(IOException ioe){
         ioe.printStackTrace();
     }
   }
}

使用org.apache.mons.io.FileUtils：

FileUtils.writeStringToFile(new File("log.txt"), "my string", Charset.defaultCharset());

private static void generateFile(String stringToWrite, String outputFile) {
    try {       
        FileWriter writer = new FileWriter(outputFile);
        writer.append(stringToWrite);
        writer.flush();
        writer.close();
        log.debug("New File is generated ==>"+outputFile);
    } catch (Exception exp) {
        log.error("Exception in generateFile ", exp);
    }
}

如果希望将字符串中的回车字符保留在文件中下面是一个代码示例：

    jLabel1 = new JLabel("Enter SQL Statements or SQL Commands:");
    orderButton = new JButton("Execute");
    textArea = new JTextArea();
    ...


    // String captured from JTextArea()
    orderButton.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent ae) {
            // When Execute button is pressed
            String tempQuery = textArea.getText();
            tempQuery = tempQuery.replaceAll("\n", "\r\n");
            try (PrintStream out = new PrintStream(new FileOutputStream("C:/Temp/tempQuery.sql"))) {
                out.print(tempQuery);
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            System.out.println(tempQuery);
        }

    });

使用Apache Commons IO中的FileUtils.writeStringToFile（）。无需重新发明这个轮子。