如何在Java中将字节大小转换为人类可读的格式?

比如1024应该变成“1 Kb”,1024*1024应该变成“1 Mb”。

我有点厌倦了为每个项目写这个实用方法。在Apache Commons中有这样的静态方法吗?


当前回答

实际上,兆字节已经足够人类阅读了。

long l = 1367343104l;
    
String s = String.format("%dm", l / 1024 / 1024);

1304米

其他回答

String[] fileSizeUnits = {"bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"};

public String calculateProperFileSize(double bytes){
    String sizeToReturn = "";
    int index = 0;
    for(index = 0; index < fileSizeUnits.length; index++){
        if(bytes < 1024){
            break;
        }
        bytes = bytes / 1024;
    }

    System.out.println("File size in proper format: " + bytes + " " + fileSizeUnits[index]);
    sizeToReturn = String.valueOf(bytes) + " " + fileSizeUnits[index];
    return sizeToReturn;
}

只需添加更多的文件单元(如果有任何缺失),你将看到单元大小达到该单元(如果你的文件有那么长):

下面是从aioobe转换到Kotlin的转换:

/**
 * https://stackoverflow.com/a/3758880/1006741
 */
fun Long.humanReadableByteCountBinary(): String {
    val b = when (this) {
        Long.MIN_VALUE -> Long.MAX_VALUE
        else -> abs(this)
    }
    return when {
        b < 1024L -> "$this B"
        b <= 0xfffccccccccccccL shr 40 -> "%.1f KiB".format(Locale.UK, this / 1024.0)
        b <= 0xfffccccccccccccL shr 30 -> "%.1f MiB".format(Locale.UK, this / 1048576.0)
        b <= 0xfffccccccccccccL shr 20 -> "%.1f GiB".format(Locale.UK, this / 1.073741824E9)
        b <= 0xfffccccccccccccL shr 10 -> "%.1f TiB".format(Locale.UK, this / 1.099511627776E12)
        b <= 0xfffccccccccccccL -> "%.1f PiB".format(Locale.UK, (this shr 10) / 1.099511627776E12)
        else -> "%.1f EiB".format(Locale.UK, (this shr 20) / 1.099511627776E12)
    }
}

我通常是这样做的:

public static String getFileSize(double size) {
    return _getFileSize(size,0,1024);
}

public static String _getFileSize(double size, int i, double base) {
    String units = " KMGTP";
    String unit = (i>0)?(""+units.charAt(i)).toUpperCase()+"i":"";
    if(size<base)
        return size +" "+unit.trim()+"B";
    else {
        size = Math.floor(size/base);
        return _getFileSize(size,++i,base);
    }
}

实际上,兆字节已经足够人类阅读了。

long l = 1367343104l;
    
String s = String.format("%dm", l / 1024 / 1024);

1304米

filename=filedilg.getSelectedFile().getAbsolutePath();
File file=new File(filename);

String disp=FileUtils.byteCountToDisplaySize(file.length());
System.out.println("THE FILE PATH IS "+file+"THIS File SIZE IS IN MB "+disp);