Java中InputSteam怎么转String

public class InputStream2String {
    public static void main(String[] args) {
        try {
            InputStream inputStream = new FileInputStream("E:/duckAndJava/io/testFile.txt");    //路径修改为本地文件所在的位置

            char[] buffer = new char[1024];    //根据需要的数组大小进行自定义
            StringBuilder out = new StringBuilder();
            Reader in = new InputStreamReader(inputStream, "UTF-8");
            for (int numRead; (numRead = in.read(buffer, 0, buffer.length)) > 0; ) {
                out.append(buffer, 0, numRead);
            }
            String myString =  out.toString();

            System.out.println("myString = " + myString);

        }catch (IOException e){
            e.printStackTrace();
        }
    }

StringBuilder sb = new StringBuilder();
for (int ch; (ch = inputStream.read()) != -1; ) {
    sb.append((char) ch);
}
String myString = sb.toString();

ByteArrayOutputStream result = new ByteArrayOutputStream();
 byte[] buffer = new byte[1024];
 for (int length; (length = inputStream.read(buffer)) != -1; ) {
     result.write(buffer, 0, length);
 }
 String myString = result.toString("UTF-8");

BufferedInputStream bis = new BufferedInputStream(inputStream);
ByteArrayOutputStream buf = new ByteArrayOutputStream();
for (int result = bis.read(); result != -1; result = bis.read()) {
    buf.write((byte) result);
}
String myString = buf.toString("UTF-8");

String newLine = System.getProperty("line.separator");
 BufferedReader reader = new BufferedReader(
         new InputStreamReader(inputStream));
 StringBuilder result = new StringBuilder();
 for (String line; (line = reader.readLine()) != null; ) {
     if (result.length() > 0) {
         result.append(newLine);
     }
     result.append(line);
 }
 String myString = result.toString();

String myString = new BufferedReader(new InputStreamReader(inputStream))
   .lines().collect(Collectors.joining("\n"));

String myString = new BufferedReader(new InputStreamReader(inputStream))

    .lines().parallel().collect(Collectors.joining("\n"));

StringWriter writer = new StringWriter();
 IOUtils.copy(inputStream, writer, "UTF-8");
 return writer.toString();

String result = CharStreams.toString(new InputStreamReader(
       inputStream, Charsets.UTF_8));