Storage Util in Java

IUnits.java

/**
 * Created by KishanDonga on 10/18/2017
 */

public interface IUnits {
    String format(long size, String pattern);

    long getUnitSize();
}

StorageUnits.java

import androidx.annotation.NonNull;

import java.text.DecimalFormat;

/**
 * Created by KishanDonga on 10/18/2017
 */

public class StorageUnits {

    private static final long K = 1024;
    private static final long M = K * K;
    private static final long G = M * K;
    private static final long T = G * K;

    public static UnitType getUnitType(long size) {
        for (Unit unit : Unit.values()) {
            if (size >= unit.getUnitSize()) {
                return UnitType.valueOf(unit.toString().toUpperCase());
            }
        }
        return UnitType.BYTE;
    }

    public static String format(long size, String pattern) {
        for (Unit unit : Unit.values()) {
            if (size >= unit.getUnitSize()) {
                return unit.format(size, pattern);
            }
        }
        return (size + " " + UnitType.BYTE.getValue());
    }

    public static String format(long size) {
        return format(size, "#,##0.#");
    }

    private enum Unit implements IUnits {
        TERA_BYTE {
            @Override
            public String format(long size, String pattern) {
                return format(size, getUnitSize(), " TB", pattern);
            }

            @Override
            public long getUnitSize() {
                return T;
            }

            @NonNull
            @Override
            public String toString() {
                return UnitType.TERABYTES.getValue();
            }
        },
        GIGA_BYTE {
            @Override
            public String format(long size, String pattern) {
                return format(size, getUnitSize(), " GB", pattern);
            }

            @Override
            public long getUnitSize() {
                return G;
            }

            @NonNull
            @Override
            public String toString() {
                return UnitType.GIGABYTES.getValue();
            }
        },
        MEGA_BYTE {
            @Override
            public String format(long size, String pattern) {
                return format(size, getUnitSize(), " MB", pattern);
            }

            @Override
            public long getUnitSize() {
                return M;
            }

            @NonNull
            @Override
            public String toString() {
                return UnitType.MEGABYTES.getValue();
            }
        },
        KILO_BYTE {
            @Override
            public String format(long size, String pattern) {
                return format(size, getUnitSize(), " KB", pattern);
            }

            @Override
            public long getUnitSize() {
                return K;
            }

            @NonNull
            @Override
            public String toString() {
                return UnitType.KILOBYTES.getValue();
            }

        };

        String format(long size, long base, String unit, String pattern) {
            return new DecimalFormat(pattern).format(
                    Long.valueOf(size).doubleValue() / Long.valueOf(base).doubleValue()
            ) + unit;
        }
    }
}

UnitType.java

public enum UnitType {

    TERABYTES("Terabytes"),
    MEGABYTES("Megabytes"),
    KILOBYTES("Kilobytes"),
    BYTE("Byte"),
    GIGABYTES("Gigabytes");

    private final String value;

    UnitType(String value) {
        this.value = value;
    }

    public String getValue() {
        return value;
    }
}

Usage:

long bytes = 10000;
StorageUnits.format(bytes);