Size.java

package marubinotto.util;

import java.io.Serializable;
import java.text.DecimalFormat;

public class Size implements Serializable {

	private long value;
	private String decimalFormat = "0.00";

	public Size(long value) {
		this.value = value;
	}

	public long getValue() {
		return value;
	}

	public double getAsGigaBytes() {
		return ByteUnit.GIGA_BYTE.convert(this.value);
	}

	public String getAsGigaBytesString() {
		DecimalFormat df = new DecimalFormat(this.decimalFormat);
		return df.format(getAsGigaBytes()) + " " + ByteUnit.GIGA_BYTE;
	}

	public double getAsMegaBytes() {
		return ByteUnit.MEGA_BYTE.convert(this.value);
	}

	public String getAsMegaBytesString() {
		DecimalFormat df = new DecimalFormat(this.decimalFormat);
		return df.format(getAsMegaBytes()) + " " + ByteUnit.MEGA_BYTE;
	}

	public double getAsKiroBytes() {
		return ByteUnit.KIRO_BYTE.convert(this.value);
	}

	public String getAsKiroBytesString() {
		DecimalFormat df = new DecimalFormat(this.decimalFormat);
		return df.format(getAsKiroBytes()) + " " + ByteUnit.KIRO_BYTE;
	}

	public String toString() {
		if (this.value > ByteUnit.GIGA_BYTE.size) {
			return getAsGigaBytesString();
		}
		else if (this.value > ByteUnit.MEGA_BYTE.size) {
			return getAsMegaBytesString();
		}
		else {
			return getAsKiroBytesString();
		}
	}

	public static class ByteUnit {
		public static final ByteUnit BYTE = new ByteUnit("byte", 1);
		public static final ByteUnit KIRO_BYTE = new ByteUnit("KByte", 1024);
		public static final ByteUnit MEGA_BYTE = new ByteUnit("MByte", 1048576);
		public static final ByteUnit GIGA_BYTE = new ByteUnit("GByte", 1073741824);

		private String name;
		private long size;

		private ByteUnit(String name, long size) {
			this.name = name;
			this.size = size;
		}

		public long getSize() {
			return size;
		}

		public double convert(long byteSize) {
			return (double)byteSize / (double)this.size;
		}

		public String toString() {
			return this.name;
		}
	}
}