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?
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
使用下面的函数来获得确切的信息。它是基于atm_cashwithdraw概念生成的。
getFullMemoryUnit(): Total: [123 MB], Max: [1 GB, 773 MB, 512 KB], Free: [120 MB, 409 KB, 304 Bytes]
public static String getFullMemoryUnit(long unit) {
long BYTE = 1024, KB = BYTE, MB = KB * KB, GB = MB * KB, TB = GB * KB;
long KILO_BYTE, MEGA_BYTE = 0, GIGA_BYTE = 0, TERA_BYTE = 0;
unit = Math.abs(unit);
StringBuffer buffer = new StringBuffer();
if ( unit / TB > 0 ) {
TERA_BYTE = (int) (unit / TB);
buffer.append(TERA_BYTE+" TB");
unit -= TERA_BYTE * TB;
}
if ( unit / GB > 0 ) {
GIGA_BYTE = (int) (unit / GB);
if (TERA_BYTE != 0) buffer.append(", ");
buffer.append(GIGA_BYTE+" GB");
unit %= GB;
}
if ( unit / MB > 0 ) {
MEGA_BYTE = (int) (unit / MB);
if (GIGA_BYTE != 0) buffer.append(", ");
buffer.append(MEGA_BYTE+" MB");
unit %= MB;
}
if ( unit / KB > 0 ) {
KILO_BYTE = (int) (unit / KB);
if (MEGA_BYTE != 0) buffer.append(", ");
buffer.append(KILO_BYTE+" KB");
unit %= KB;
}
if ( unit > 0 ) buffer.append(", "+unit+" Bytes");
return buffer.toString();
}
我刚刚修改了facebookarchive-StringUtils的代码以获得以下格式。与使用apache.hadoop-StringUtils时得到的格式相同
getMemoryUnit(): Total: [123.0 MB], Max: [1.8 GB], Free: [120.4 MB]
public static String getMemoryUnit(long bytes) {
DecimalFormat oneDecimal = new DecimalFormat("0.0");
float BYTE = 1024.0f, KB = BYTE, MB = KB * KB, GB = MB * KB, TB = GB * KB;
long absNumber = Math.abs(bytes);
double result = bytes;
String suffix = " Bytes";
if (absNumber < MB) {
result = bytes / KB;
suffix = " KB";
} else if (absNumber < GB) {
result = bytes / MB;
suffix = " MB";
} else if (absNumber < TB) {
result = bytes / GB;
suffix = " GB";
}
return oneDecimal.format(result) + suffix;
}
以上方法的使用示例:
public static void main(String[] args) {
Runtime runtime = Runtime.getRuntime();
int availableProcessors = runtime.availableProcessors();
long heapSize = Runtime.getRuntime().totalMemory();
long heapMaxSize = Runtime.getRuntime().maxMemory();
long heapFreeSize = Runtime.getRuntime().freeMemory();
System.out.format("Total: [%s], Max: [%s], Free: [%s]\n", heapSize, heapMaxSize, heapFreeSize);
System.out.format("getMemoryUnit(): Total: [%s], Max: [%s], Free: [%s]\n",
getMemoryUnit(heapSize), getMemoryUnit(heapMaxSize), getMemoryUnit(heapFreeSize));
System.out.format("getFullMemoryUnit(): Total: [%s], Max: [%s], Free: [%s]\n",
getFullMemoryUnit(heapSize), getFullMemoryUnit(heapMaxSize), getFullMemoryUnit(heapFreeSize));
}
字节来获取上面的格式
Total: [128974848], Max: [1884815360], Free: [126248240]
为了以人类可读的格式显示时间,请使用函数millisToShortDHMS(长持续时间)。
其他回答
你可以使用StringUtils的TraditionalBinarPrefix:
public static String humanReadableInt(long number) {
return TraditionalBinaryPrefix.long2String(number, ””, 1);
}
public String humanReadable(long size) {
long limit = 10 * 1024;
long limit2 = limit * 2 - 1;
String negative = "";
if(size < 0) {
negative = "-";
size = Math.abs(size);
}
if(size < limit) {
return String.format("%s%s bytes", negative, size);
} else {
size = Math.round((double) size / 1024);
if (size < limit2) {
return String.format("%s%s kB", negative, size);
} else {
size = Math.round((double)size / 1024);
if (size < limit2) {
return String.format("%s%s MB", negative, size);
} else {
size = Math.round((double)size / 1024);
if (size < limit2) {
return String.format("%s%s GB", negative, size);
} else {
size = Math.round((double)size / 1024);
return String.format("%s%s TB", negative, size);
}
}
}
}
}
这是另一个简洁的解决方案,没有循环,但具有区域敏感格式和正确的二进制前缀:
import java.util.Locale;
public final class Bytes {
private Bytes() {
}
public static String format(long value, Locale locale) {
if (value < 1024) {
return value + " B";
}
int z = (63 - Long.numberOfLeadingZeros(value)) / 10;
return String.format(locale, "%.1f %siB", (double) value / (1L << (z * 10)), " KMGTPE".charAt(z));
}
}
测试:
Locale locale = Locale.getDefault()
System.out.println(Bytes.format(1L, locale))
System.out.println(Bytes.format(2L * 1024, locale))
System.out.println(Bytes.format(3L * 1024 * 1024, locale))
System.out.println(Bytes.format(4L * 1024 * 1024 * 1024, locale))
System.out.println(Bytes.format(5L * 1024 * 1024 * 1024 * 1024, locale))
System.out.println(Bytes.format(6L * 1024 * 1024 * 1024 * 1024 * 1024, locale))
System.out.println(Bytes.format(Long.MAX_VALUE, locale))
输出:
1 B
2.0 KiB
3.0 MiB
4.0 GiB
5.0 GiB
6.0 PiB
8.0 EiB
也许你可以使用下面的代码(在c#中):
long Kb = 1024;
long Mb = Kb * 1024;
long Gb = Mb * 1024;
long Tb = Gb * 1024;
long Pb = Tb * 1024;
long Eb = Pb * 1024;
if (size < Kb) return size.ToString() + " byte";
if (size < Mb) return (size / Kb).ToString("###.##") + " Kb.";
if (size < Gb) return (size / Mb).ToString("###.##") + " Mb.";
if (size < Tb) return (size / Gb).ToString("###.##") + " Gb.";
if (size < Pb) return (size / Tb).ToString("###.##") + " Tb.";
if (size < Eb) return (size / Pb).ToString("###.##") + " Pb.";
if (size >= Eb) return (size / Eb).ToString("###.##") + " Eb.";
return "invalid size";
试试JSR 363。它的单元扩展模块,如Unicode CLDR(在GitHub: uom-systems中),为您完成所有这些。
你可以使用每个实现中包含的MetricPrefix或BinaryPrefix(与上面的一些例子相比),如果你在印度或附近的国家生活和工作,IndianPrefix(也在uom-系统的公共模块中)允许你使用和格式化“千万字节”或“Lakh字节”。