Test.java

package test;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class Test {

	public static void main(final String[] args) {
		Test t = new Test();
		A a = t.init();
		t.recFunction(a, 0);
	}

	public boolean recFunction(final A element, final int level) {
		boolean result = false;

		System.out.println("PARSING: " + element.getId());

		if (level == 2) {
			result = true;
		}

		if (element.getChildren() != null) {
			for (Iterator<A> iterator = element.getChildren().iterator(); iterator.hasNext();) {
				A child = iterator.next();
				System.out.println("CHILD:" + child.getId());
                                boolean tmp = recFunction(child, level + 1);
				System.out.println("Result for :" + child.getId() + " is " + tmp);
				//result = result || recFunction(child, level + 1);

			}
		}

		return result;
	}

	public A init() {
		/*
		 * a |_ 1a |_ 2a-a [_ 2a-b |_ 1b |_ 2b-a |_ 2b-b
		 */

		A a = new A("a");

		List<A> list = new ArrayList<A>();

		A son1a = new A("1a");
		List<A> subList = new ArrayList<A>();
		subList.add(new A("2a-a"));
		subList.add(new A("2a-b"));
		son1a.setChildren(subList);

		A son1b = new A("1b");
		List<A> subList2 = new ArrayList<A>();
		subList2.add(new A("2b-a"));
		subList2.add(new A("2b-b"));
		son1b.setChildren(subList2);

		list.add(son1a);
		list.add(son1b);

		a.setChildren(list);

		return a;
	}

	public class A {
		private List<A> children;

		private String id;

		public A(final String id) {
			setId(id);
		}

		public String getId() {
			return id;
		}

		public void setId(final String id) {
			this.id = id;
		}

		public List<A> getChildren() {
			return children;
		}

		public void setChildren(final List<A> children) {
			this.children = children;
		}
	}
}

Sur l'instruction result = result || recFunction(child, level + 1); arrive un moment ou la variable result vaut true, donc cassant la récursivité au premier élement identifié de level 2.