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Samples used in documenting the jADT project

There is a newer version: 0.3.0

/*
Copyright 2012 James Iry

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.
*/
package com.pogofish.jadt.samples.whathow;

import com.pogofish.jadt.samples.whathow.data.BinaryTree;
import com.pogofish.jadt.samples.whathow.data.BinaryTree.*;

import static com.pogofish.jadt.samples.whathow.data.BinaryTree.*;

/**
 * Example usage of an GenericBinaryTree used in the how page
 * It is marked up with START SNIPPET and END SNIPPET boundaries to support
 * /jADT/src/site/apt/*.apt
 * 
 * @author jiry
 */
public class GenericBinaryTreeUsage {
    /**
     * Creates an example IntBinaryTree with some fixed values
     */
    public BinaryTree createExample() {
        // START SNIPPET: sampleTree
        BinaryTree empty = BinaryTree._EmptyTree();

        return _Node("hello", _Node("goodbye", empty, empty), _Node("whatever", empty, _Node("foo", empty, empty)));        
        // END SNIPPET: sampleTree
    } 
    
    /**
     * Find the string that sorts highest in a tree where null 
     * is considered smallest and otherwise strings are compared with compareTo
     */
    // START SNIPPET: max
    public String max(BinaryTree tree)  {
        return tree.match(new BinaryTree.MatchBlock() {
           @Override
           public String _case(Node x) {
               final String maxLeft = max(x.left);
               final String maxRight = max(x.right);

               return maxString(maxString(maxLeft, maxRight), x.value);
           }

           @Override
           public String _case(EmptyTree x) {
              return null;
           }
        });
     }
    
    private String maxString(String l, String r) {
        return l == null ? r : (r == null ? l : (l.compareTo(r) >= 0 ? l : r));
    }
    // END SNIPPET: max
}