public class TestSizeToHuman {
public static void main(String[] args) {
String str=MyCommonTool.readableFileSize(123456);
System.out.println("str="+str);
String line=org.apache.commons.io.FileUtils.byteCountToDisplaySize(123456);
System.out.println("line="+line);
ByteSizeValue byteSizeValue=new ByteSizeValue(123456, ByteSizeUnit.BYTES);
System.out.println("byteSizeValue="+byteSizeValue.getKbFrac()+" KB");
System.out.println("byteSizeValue="+byteSizeValue.getMbFrac()+" MB");
}
}
import java.text.DecimalFormat;
public class MyCommonTool {
public static String readableFileSize(long size) {
if (size <= 0) {
return "0";
}
final String[] units = new String[]{"B", "kB", "MB", "GB", "TB"};
int digitGroups = (int) (Math.log10(size) / Math.log10(1024));
return new DecimalFormat("#,##0.#").format(size / Math.pow(1024, digitGroups)) + " " + units[digitGroups];
}
}
import java.io.Serializable;
import java.util.Locale;
public class ByteSizeValue implements Serializable {
private long size;
private ByteSizeUnit sizeUnit;
private ByteSizeValue() {
}
public ByteSizeValue(long bytes) {
this(bytes, ByteSizeUnit.BYTES);
}
public ByteSizeValue(long size, ByteSizeUnit sizeUnit) {
this.size = size;
this.sizeUnit = sizeUnit;
}
public int bytesAsInt() throws Exception {
long bytes = bytes();
if (bytes > Integer.MAX_VALUE) {
throw new Exception("size [" + toString() + "] is bigger than max int");
}
return (int) bytes;
}
public long bytes() {
return sizeUnit.toBytes(size);
}
public long getBytes() {
return bytes();
}
public long kb() {
return sizeUnit.toKB(size);
}
public long getKb() {
return kb();
}
public long mb() {
return sizeUnit.toMB(size);
}
public long getMb() {
return mb();
}
public long gb() {
return sizeUnit.toGB(size);
}
public long getGb() {
return gb();
}
public long tb() {
return sizeUnit.toTB(size);
}
public long getTb() {
return tb();
}
public long pb() {
return sizeUnit.toPB(size);
}
public long getPb() {
return pb();
}
public double kbFrac() {
return ((double) bytes()) / ByteSizeUnit.C1;
}
public double getKbFrac() {
return kbFrac();
}
public double mbFrac() {
return ((double) bytes()) / ByteSizeUnit.C2;
}
public double getMbFrac() {
return mbFrac();
}
public double gbFrac() {
return ((double) bytes()) / ByteSizeUnit.C3;
}
public double getGbFrac() {
return gbFrac();
}
public double tbFrac() {
return ((double) bytes()) / ByteSizeUnit.C4;
}
public double getTbFrac() {
return tbFrac();
}
public double pbFrac() {
return ((double) bytes()) / ByteSizeUnit.C5;
}
public double getPbFrac() {
return pbFrac();
}
/**
* Format the double value with a single decimal points, trimming trailing '.0'.
*/
public static String format1Decimals(double value, String suffix) {
String p = String.valueOf(value);
int ix = p.indexOf('.') + 1;
int ex = p.indexOf('E');
char fraction = p.charAt(ix);
if (fraction == '0') {
if (ex != -1) {
return p.substring(0, ix - 1) + p.substring(ex) + suffix;
} else {
return p.substring(0, ix - 1) + suffix;
}
} else {
if (ex != -1) {
return p.substring(0, ix) + fraction + p.substring(ex) + suffix;
} else {
return p.substring(0, ix) + fraction + suffix;
}
}
}
@Override
public String toString() {
long bytes = bytes();
double value = bytes;
String suffix = "b";
if (bytes >= ByteSizeUnit.C5) {
value = pbFrac();
suffix = "pb";
} else if (bytes >= ByteSizeUnit.C4) {
value = tbFrac();
suffix = "tb";
} else if (bytes >= ByteSizeUnit.C3) {
value = gbFrac();
suffix = "gb";
} else if (bytes >= ByteSizeUnit.C2) {
value = mbFrac();
suffix = "mb";
} else if (bytes >= ByteSizeUnit.C1) {
value = kbFrac();
suffix = "kb";
}
return format1Decimals(value, suffix);
}
public static ByteSizeValue parseBytesSizeValue(String sValue) throws Exception {
return parseBytesSizeValue(sValue, null);
}
public static ByteSizeValue parseBytesSizeValue(String sValue, ByteSizeValue defaultValue) throws Exception {
if (sValue == null) {
return defaultValue;
}
long bytes;
try {
String lastTwoChars = sValue.substring(sValue.length() - Math.min(2, sValue.length())).toLowerCase(Locale.ROOT);
if (lastTwoChars.endsWith("k")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 1)) * ByteSizeUnit.C1);
} else if (lastTwoChars.endsWith("kb")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 2)) * ByteSizeUnit.C1);
} else if (lastTwoChars.endsWith("m")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 1)) * ByteSizeUnit.C2);
} else if (lastTwoChars.endsWith("mb")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 2)) * ByteSizeUnit.C2);
} else if (lastTwoChars.endsWith("g")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 1)) * ByteSizeUnit.C3);
} else if (lastTwoChars.endsWith("gb")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 2)) * ByteSizeUnit.C3);
} else if (lastTwoChars.endsWith("t")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 1)) * ByteSizeUnit.C4);
} else if (lastTwoChars.endsWith("tb")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 2)) * ByteSizeUnit.C4);
} else if (lastTwoChars.endsWith("p")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 1)) * ByteSizeUnit.C5);
} else if (lastTwoChars.endsWith("pb")) {
bytes = (long) (Double.parseDouble(sValue.substring(0, sValue.length() - 2)) * ByteSizeUnit.C5);
} else if (lastTwoChars.endsWith("b")) {
bytes = Long.parseLong(sValue.substring(0, sValue.length() - 1));
} else {
bytes = Long.parseLong(sValue);
}
} catch (NumberFormatException e) {
throw new Exception("Failed to parse [" + sValue + "]", e);
}
return new ByteSizeValue(bytes, ByteSizeUnit.BYTES);
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
ByteSizeValue sizeValue = (ByteSizeValue) o;
if (size != sizeValue.size) return false;
if (sizeUnit != sizeValue.sizeUnit) return false;
return true;
}
@Override
public int hashCode() {
int result = (int) (size ^ (size >>> 32));
result = 31 * result + (sizeUnit != null ? sizeUnit.hashCode() : 0);
return result;
}
}
public enum ByteSizeUnit {
BYTES {
@Override
public long toBytes(long size) {
return size;
}
@Override
public long toKB(long size) {
return size / (C1 / C0);
}
@Override
public long toMB(long size) {
return size / (C2 / C0);
}
@Override
public long toGB(long size) {
return size / (C3 / C0);
}
@Override
public long toTB(long size) {
return size / (C4 / C0);
}
@Override
public long toPB(long size) {
return size / (C5 / C0);
}
},
KB {
@Override
public long toBytes(long size) {
return x(size, C1 / C0, MAX / (C1 / C0));
}
@Override
public long toKB(long size) {
return size;
}
@Override
public long toMB(long size) {
return size / (C2 / C1);
}
@Override
public long toGB(long size) {
return size / (C3 / C1);
}
@Override
public long toTB(long size) {
return size / (C4 / C1);
}
@Override
public long toPB(long size) {
return size / (C5 / C1);
}
},
MB {
@Override
public long toBytes(long size) {
return x(size, C2 / C0, MAX / (C2 / C0));
}
@Override
public long toKB(long size) {
return x(size, C2 / C1, MAX / (C2 / C1));
}
@Override
public long toMB(long size) {
return size;
}
@Override
public long toGB(long size) {
return size / (C3 / C2);
}
@Override
public long toTB(long size) {
return size / (C4 / C2);
}
@Override
public long toPB(long size) {
return size / (C5 / C2);
}
},
GB {
@Override
public long toBytes(long size) {
return x(size, C3 / C0, MAX / (C3 / C0));
}
@Override
public long toKB(long size) {
return x(size, C3 / C1, MAX / (C3 / C1));
}
@Override
public long toMB(long size) {
return x(size, C3 / C2, MAX / (C3 / C2));
}
@Override
public long toGB(long size) {
return size;
}
@Override
public long toTB(long size) {
return size / (C4 / C3);
}
@Override
public long toPB(long size) {
return size / (C5 / C3);
}
},
TB {
@Override
public long toBytes(long size) {
return x(size, C4 / C0, MAX / (C4 / C0));
}
@Override
public long toKB(long size) {
return x(size, C4 / C1, MAX / (C4 / C1));
}
@Override
public long toMB(long size) {
return x(size, C4 / C2, MAX / (C4 / C2));
}
@Override
public long toGB(long size) {
return x(size, C4 / C3, MAX / (C4 / C3));
}
@Override
public long toTB(long size) {
return size;
}
@Override
public long toPB(long size) {
return size / (C5 / C4);
}
},
PB {
@Override
public long toBytes(long size) {
return x(size, C5 / C0, MAX / (C5 / C0));
}
@Override
public long toKB(long size) {
return x(size, C5 / C1, MAX / (C5 / C1));
}
@Override
public long toMB(long size) {
return x(size, C5 / C2, MAX / (C5 / C2));
}
@Override
public long toGB(long size) {
return x(size, C5 / C3, MAX / (C5 / C3));
}
@Override
public long toTB(long size) {
return x(size, C5 / C4, MAX / (C5 / C4));
}
@Override
public long toPB(long size) {
return size;
}
};
static final long C0 = 1L;
static final long C1 = C0 * 1024L;
static final long C2 = C1 * 1024L;
static final long C3 = C2 * 1024L;
static final long C4 = C3 * 1024L;
static final long C5 = C4 * 1024L;
static final long MAX = Long.MAX_VALUE;
/**
* Scale d by m, checking for overflow.
* This has a short name to make above code more readable.
*/
static long x(long d, long m, long over) {
if (d > over) return Long.MAX_VALUE;
if (d < -over) return Long.MIN_VALUE;
return d * m;
}
public abstract long toBytes(long size);
public abstract long toKB(long size);
public abstract long toMB(long size);
public abstract long toGB(long size);
public abstract long toTB(long size);
public abstract long toPB(long size);
}
转自： http://blog.csdn.net/earbao/article/details/50037319