以当前默认file encoding读取文件然后以utf-8写入新文件

曾经终败给现在 2022-08-18 13:17 41阅读 0赞

在简体中文Windows上， 默认启动的Java程序如果没有加上设置file encoding，那么默认生成的文件(写文件时没有指定编码的那种)是GBK编码的，这样的文件传输到其它非GBK编码的机器上会无法正常显示。 需要将其转换为utf-8格式的，这样就能在所有机器上以utf-8打开正常显示。

下面这段代码是如何将文件从当前默认的encoding读取后以utf-8写入

读取当前的file encodning  (注意xxx.java文件是utf-8编码)

String fileEncoding = System.getProperty("file.encoding");  
          System.out.println("FileEncoding:" + fileEncoding);

try {
            	 String filePath= "d:\\dir1\\file1.txt";
                 File readfile = new File(filePath);
    
                 if (readfile.isFile() && readfile.exists()) {
                	 //按照当前默认的file encoding独舞文件
                     InputStreamReader read = new InputStreamReader(new FileInputStream(readfile));
                     System.out.println("File Encoding:["+ read.getEncoding());
                     BufferedReader bufferedReader = new BufferedReader(read);
                     String lineTxt = null; 
                     StringBuilder sb = new StringBuilder();
    
                     while ((lineTxt = bufferedReader.readLine()) != null) {
                    	 sb.append(lineTxt).append("\n");
                     }
                     read.close();
                     System.out.println("New:" + sb.toString());
                     
                     File fileWriter = new File(filePath + "a");
                     if (fileWriter != null && fileWriter.exists()) {
                         System.out.println("File["+fileWriter.getAbsolutePath() + "] already exists, Will not create it");
                     }
                     else {
                         System.out.println("File["+fileWriter.getAbsolutePath() + "] does not exists, create it");
                         //以utf-8写入文件
                         Writer out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileWriter), "UTF-8"));
    
                         try {
                             out.write(sb.toString());
                         } finally {
                             out.close();
                         }
                     }
                     
                 } 
                 else {
                     System.out.println("File:["+ readfile.getAbsolutePath() +"] does non exist");
                 }
                 
             } catch (Exception e) {
                 System.out.println("error");
                 e.printStackTrace();
             }

可以在启动java程序时改变file enconding

set JAVA\_OPTS=-Xmx512m    -Dfile.encoding=UTF-8

或者java -jar  xxxx  -Dfile.encoding=UTF-8