One option to implement Comparable.compareTo()

compareTo.java

// I haven't tested it
public int compareTo(MyClass that) {
	if (this == that) return 0;
	int comp = Integer.valueOf(this.intField).compareTo(that.intField);
	if (comp != 0) return comp;
	comp = this.stringField == null ? -1 : this.claveRed.compareTo(that.stringField);
	if (comp != 0) return comp;
	comp = Boolean.valueOf(this.booleanField).compareTo(that.booleanField);
	if (comp != 0) return comp;
	comp = this.objectField == null ? -1 : this.claveRed.compareTo(that.objectField);
	return comp;
}