iWIN 必須被解散!

Weil Jimmer's BlogWeil Jimmer's Blog


Java【解決方法】Byte[]、UByte[]的問題 Byte有負號
No Comments

發布:
更新:2016-01-06 18:37:17

    String str = "這是測試!ABC123.";
    byte[] bytes = {};
    try {
        bytes = str.getBytes("UTF-8");
    }catch(Exception ex){
    }
    for(int i=0;i<bytes.length;i++){
        System.out.println(bytes[i]);
    }
    System.out.println(bytes);

我們都知道,其實,Java裡面本身並不支援Ubyte。若真要使用差不多的功能,建議可以改用Short。

Ubyte就是沒有負號,而Byte就是可能會有負號。跟轉成二進制之後的高位補數與否有關係的樣子。

在此提供解決方法。直接看Code。

    //將字串以UTF8編碼轉成Ubyte[](實際上是short[]型別)
    public static short[] StringtoUByte(String str) {
        byte[] bytes = {};
        try {
            bytes = str.getBytes("UTF-8");
        }catch(UnsupportedEncodingException ex){

        }
        return BytetoUByte(bytes);
    }

    //將Ubyte[]以UTF8編碼轉成字串(實際上是short[]型別轉成字串)
    public static String UBytetoString(short[] ubytes) {
        byte[] bytes = UBytetoByte(ubytes);
        String str = "";
        try{
            str = new String(bytes,"UTF-8");
        }catch (Exception ex){

        }
        return str;
    }

    //將Ubyte[]轉成byte[](將short[]轉成byte[])
    public static byte[] UBytetoByte(short[] ubytes) {
        byte[] bytes = new byte[ubytes.length];
        for(int i=0;i<bytes.length;i++){
            bytes[i]=signedToBytes(ubytes[i]);
        }
        return bytes;
    }

    //將byte[]轉成Ubyte[](將byte[]轉成short[])
    public static short[] BytetoUByte(byte[] bytes) {
        short[] ubytes = new short[bytes.length];
        for(int i=0;i<bytes.length;i++){
            ubytes[i]=unsignedToBytes(bytes[i]);
        }
        return ubytes;
    }

    //將byte轉成Ubyte(將byte轉成short)
    public static short unsignedToBytes(byte b) {
        return (short)(b & 0xFF);
    }

    //將Ubyte轉成byte(將int轉成byte)
    public static byte signedToBytes(int b) {
        return ((byte)(b & 0xFF));
    }

可能看官們都注意到,byte轉ubyte都是 一樣的寫法。==> b & 0xFF

只是給他加個二進位負號而已,再加一個負號又變回原樣了。So,解釋完畢,上面的代碼自行取用吧。


This entry was posted in Java, Note By Weil Jimmer.

About Weil Jimmer

avatar

Hi! Everyone! My name is Weil Jimmer. This is my personal blog. I'm a webmaster of this site. I hope the site will be popular. Now, Let's go! Enjoy gaining more knowledge.
More Details About Me : https://weils.net/profile.php

Leave a Reply

Name*:

Email*:

Website:

Privacy:   

Comment*:

Visitor Count

pop
nonenonenone

Note

支持網路中立性.
Support Net Neutrality.

飽暖思淫欲,饑寒起盜心。

支持臺灣實施無條件基本收入

歡迎前來本站。

Words Quiz


Search

Music

Blogging Journey

4227days

since our first blog post.

Republic Of China
The strong do what they can and the weak suffer what they must.

Privacy is your right and ability to be yourself and express yourself without the fear that someone is looking over your shoulder and that you might be punished for being yourself, whatever that may be.

It is quality rather than quantity that matters.

I WANT Internet Freedom.

Reality made most of people lost their childishness.

Justice,Freedom,Knowledge.

Without music life would be a mistake.

Support/Donate

This site also need a little money to maintain operations, not entirely without any cost in the Internet. Your donations will be the best support and power of the site.
MethodBitcoin Address
bitcoin1gtuwCjjVVrNUHPGvW6nsuWGxSwygUv4x
buymeacoffee
Register in linode via invitation link and stay active for three months.Linode

Support The Zeitgeist Movement

The Zeitgeist Movement

The Lie We Live

The Lie We Live

The Questions We Never Ask

The Questions We Never Ask

Man

Man

THE EMPLOYMENT

Man

In The Fall

In The Fall

Facebook is EATING the Internet

Facebook

Categories

Android (7)

Announcement (4)

Arduino (2)

Bash (2)

C (3)

C# (5)

C++ (1)

Experience (50)

Flash (2)

Free (13)

Functions (36)

Games (13)

General (57)

HTML (7)

Java (13)

JS (7)

Mood (24)

Note (30)

Office (1)

OpenWrt (5)

PHP (9)

Privacy (4)

Product (12)

Python (4)

Software (11)

The Internet (24)

Tools (16)

VB.NET (8)

WebHosting (7)

Wi-Fi (5)

XML (4)