TestRandom.java

package test;

import java.util.Arrays;
import java.util.Random;
import java.util.stream.Collectors;

public class TestRandom extends Random {

	private static final long serialVersionUID = 1L;

	public static enum DebugLevel {
		OFF, SEED_ONLY, FINE, FINER, FINEST;

		public boolean canLog(DebugLevel level) {
			return ordinal() >= level.ordinal();
		}
	}

	private DebugLevel debugLevel = DebugLevel.OFF;
	private int sequenceCount = 0;

	public TestRandom() {
		super();
	}

	public TestRandom(long seed) {
		super(seed);
	}

	public int getSequenceCount() {
		return sequenceCount;
	}

	public void resetSequenceCount() {
		sequenceCount = 0;
	}

	public void setDebugLevel(DebugLevel level) {
		this.debugLevel = level;
	}

	public DebugLevel getDebugLevel() {
		return debugLevel;
	}

	@Override
	protected int next(int bits) {
		sequenceCount++;
		return super.next(bits);
	}

	@Override
	public int nextInt() {
		if (debugLevel.canLog(DebugLevel.FINER))
			System.out.println(getCaller() + " Random.nextInt()");
		return super.nextInt();
	}

	@Override
	public int nextInt(int bound) {
		if (debugLevel.canLog(DebugLevel.FINER))
			System.out.println(getCaller() + " Random.nextInt(" + bound + ")");
		return super.nextInt(bound);
	}

	@Override
	public long nextLong() {
		if (debugLevel.canLog(DebugLevel.FINER))
			System.out.println(getCaller() + " Random.nextLong()");
		return super.nextLong();
	}

	@Override
	public boolean nextBoolean() {
		if (debugLevel.canLog(DebugLevel.FINER))
			System.out.println(getCaller() + " Random.nextBoolean()");
		return super.nextBoolean();
	}

	@Override
	public float nextFloat() {
		if (debugLevel.canLog(DebugLevel.FINER))
			System.out.println(getCaller() + " Random.nextFloat()");
		return super.nextFloat();
	}

	@Override
	public double nextDouble() {
		if (debugLevel.canLog(DebugLevel.FINER))
			System.out.println(getCaller() + " Random.nextDouble()");
		return super.nextDouble();
	}

	@Override
	public synchronized double nextGaussian() {
		if (debugLevel.canLog(DebugLevel.FINER))
			System.out.println(getCaller() + " Random.nextGaussian()");
		return super.nextGaussian();
	}

	@Override
	public void setSeed(long seed) {
		if (debugLevel != null && debugLevel.canLog(DebugLevel.SEED_ONLY))
			System.out.println(getCaller() + " Random.setSeed(" + seed + ")");
		super.setSeed(seed);
		resetSequenceCount();
	}

	private String getCaller() {
		if (!debugLevel.canLog(DebugLevel.FINEST))
			return "";
		StackTraceElement[] stackTrace = Thread.currentThread().getStackTrace();
		for (int i = 0; i < stackTrace.length / 2; i++) {
			StackTraceElement tmp = stackTrace[i];
			stackTrace[i] = stackTrace[stackTrace.length - i - 1];
			stackTrace[stackTrace.length - i - 1] = tmp;
		}
		return Arrays.stream(stackTrace).limit(stackTrace.length - 3).map(String::valueOf)
				.collect(Collectors.joining(" ||| "));
	}

}