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diff --git a/rosetta/src/main/java/com/att/rosetta/Ladder.java b/rosetta/src/main/java/com/att/rosetta/Ladder.java
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+/*******************************************************************************
+ * ============LICENSE_START====================================================
+ * * org.onap.aai
+ * * ===========================================================================
+ * * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
+ * * Copyright © 2017 Amdocs
+ * * ===========================================================================
+ * * Licensed under the Apache License, Version 2.0 (the "License");
+ * * you may not use this file except in compliance with the License.
+ * * You may obtain a copy of the License at
+ * * 
+ *  *      http://www.apache.org/licenses/LICENSE-2.0
+ * * 
+ *  * Unless required by applicable law or agreed to in writing, software
+ * * distributed under the License is distributed on an "AS IS" BASIS,
+ * * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * * See the License for the specific language governing permissions and
+ * * limitations under the License.
+ * * ============LICENSE_END====================================================
+ * *
+ * * ECOMP is a trademark and service mark of AT&T Intellectual Property.
+ * *
+ ******************************************************************************/
+package com.att.rosetta;
+
+
+/**
+ * A Ladder is a Stack like Storage Class, but where you can ascend and descend while
+ * the elements exists.
+ * 
+ * Like an extension ladder, you can make taller as you go
+ * 
+ *
+ */
+public class Ladder<T> {
+	public static final int DEFAULT_INIT_SIZE=8;
+	private final int init_size;
+	private int rung; // as in ladder
+	private Object[] struts;
+
+	public Ladder() {
+		rung=0;
+		init_size = DEFAULT_INIT_SIZE;
+		struts=new Object[init_size];
+	}
+
+	public Ladder(int initSize) {
+		rung=0;
+		init_size = initSize;
+		struts=new Object[init_size];
+	}
+
+	public void bottom() {
+		rung = 0;
+	}
+	
+	public void top() {
+		rung = struts.length-1;
+		while(rung>0 && struts[rung]==null)--rung;
+	}
+	
+	public int howHigh() {
+		return rung;
+	}
+	
+	public void jumpTo(int rung) {
+		if(rung>=struts.length) {
+			Object[] temp = new Object[init_size*((rung/init_size)+1)];
+			System.arraycopy(struts, 0, temp, 0, struts.length);
+			struts = temp;
+		}
+		this.rung = rung;
+	}
+	
+	public int height() {
+		return struts.length;
+	}
+	
+	public void cutTo(int rungs) {
+		Object[] temp = new Object[rungs];
+		System.arraycopy(struts, 0, temp, 0, Math.min(rungs, struts.length));
+		struts = temp;
+	}
+	
+	public void ascend() {
+		++rung;
+		if(rung>=struts.length) {
+			Object[] temp = new Object[struts.length+init_size];
+			System.arraycopy(struts, 0, temp, 0, struts.length);
+			struts = temp;
+		}
+	}
+	
+	public void descend() {
+		--rung;
+	}
+	
+	@SuppressWarnings("unchecked")
+	public T peek() {
+		return (T)struts[rung];
+	}
+	
+	public void push(T t) {
+		struts[rung]=t;
+	}
+	
+	@SuppressWarnings("unchecked")
+	public T pop() {
+		T t = (T)struts[rung];
+		struts[rung]=null;
+		return t;
+	}
+
+}