从套接字intputStream read（）返回的Int中获取字节

Question

这是我的代码

private static Packet readPacket(InputStream is) throws Exception
{
    int ch;
    Packet p = new Packet();

    String type = "";
    while((ch = is.read()) != 44) //44 is the "," in ISO-8859-1 codification
    {
        if(ch == -1)
            throw new IOException("EOF");
        type += new String(ch, "ISO-8859-1"); //<----DOES NOT COMPILE
    }
    ...
}

字符串构造函数不接收int,只接收字节数组.我看了文件上面说

read（）：从输入流中读取下一个字节的数据。

Answer 1

String构造函数采用char[]（数组）

type += new String(new byte[] { (byte) ch }, "ISO-8859-1");

顺便说一句。使用StringBuilder作为类型并使用它的append-methods会更好。它更快，也更好地显示了意图：

private static Packet readPacket(InputStream is) throws Exception {
    int ch;
    Packet p = new Packet();

    StringBuilder type = new StringBuilder();
    while((ch = is.read()) != 44) {
        if(ch == -1)
            throw new IOException("EOF");
        // NOTE: conversion from byte to char here is iffy, this works for ISO8859-1/US-ASCII
        // but fails horribly for UTF etc.
        type.append((char) ch);
    }
    String data = type.toString();
    ...
}

此外，为了使其更加灵活（例如，使用其他字符编码），您的方法最好使用一个InputStreamReader，它可以为您处理从字节到字符的转换（看看InputStreamReader(InputStream，Charset)构造函数的javadoc）。