如何在Java中将FileInputStream转换为字符串？

您不能直接将其转换为字符串。您应该实现这样的东西将此代码添加到您的方法中

    //Commented this out because this is not the efficient way to achieve that    //StringBuilder builder = new StringBuilder();    //int ch;    //while((ch = fis.read()) != -1){    //  builder.append((char)ch);    //}    //   //System.out.println(builder.toString());

使用Aubin的解决方案：

public static String getFileContent(   FileInputStream fis,   String          encoding ) throws IOException {   try( BufferedReader br =new BufferedReader( new InputStreamReader(fis, encoding )))   {      StringBuilder sb = new StringBuilder();      String line;      while(( line = br.readLine()) != null ) {         sb.append( line );         sb.append( 'n' );      }      return sb.toString();   }}