Talk is cheap, Show me the code. — by: Linus Torvalds

方式一、

Java8+ Stream API

 String result = new BufferedReader(new InputStreamReader(inputStream))
    .lines() // 按行读取
    .collect(Collectors.joining("\n")); // 合并行为字符串  

方式二、

使用commons-io

 String result = IOUtils.toString(inputStream, "UTF-8");  

方式三、

使用Guava

 String result = CharStreams.toString(new InputStreamReader(inputStream, "UTF-8"));  

方式四、

使用ByteArrayOutputStream

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