uimaj-core/src/test/java/org/apache/uima/internal/util/Int2ObjHashMapTest.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.uima.internal.util;

import java.util.Random;

import org.apache.uima.util.IntEntry;

import junit.framework.TestCase;

public class Int2ObjHashMapTest extends TestCase {
  
  // a number of extras needed to cause rebalance
  // is > 1 because it might turn out randomly that
  // the puts clear all the REMOVED_KEY values
  // needs to be > than 1/2 the capacity/2
  private static final int  REBAL = 32;  

  Int2ObjHashMap<Integer, Integer> ihm;
  
  public void setUp() {
    ihm = new Int2ObjHashMap<>(Integer.class);
  }

  public void testBasic() {
    
    ihm.put(15, 150);
    ihm.put(188, 1880);
    assertEquals(2, ihm.size());
    assertEquals(150, (int)ihm.get(15));
    assertEquals(1880, (int)ihm.get(188));

    assertEquals(null, ihm.remove(18));
    assertEquals(150, (int)ihm.remove(15));
    assertEquals(1, ihm.size());
    
    for (IntEntry<Integer> ie : ihm) {
      assertEquals(ie.getKey(), 188);
    }
    
    assertEquals(1880, (int)ihm.remove(188));
    assertEquals(0, ihm.size());
    for (IntEntry<Integer> ie : ihm) {
      fail();  // should be empty
    }
    
  }
  
  public void testRebalance() {
    // 100 elements, require 256 table (128 * .66 = 85)
    for (int i = 1; i < 101; i++) {
      ihm.put(i, i * 10);
    }
    
    // have 100 elements, remove 100 elements
    for (int i = 1; i < 101; i++) {
      assertEquals(i*10, (int)ihm.remove(i));
    }
    
    
    assertEquals(0, ihm.size());
    
    assertEquals(64, ihm.getCapacity());
    
    for (int i = 1; i < 101 + REBAL; i++) {
      ihm.put(i + 100, i * 10);  // add different keys, so may use some new slots
    }
    
    assertEquals(256, ihm.getCapacity()); //because above are different adds, likely into non-removed positions
    
    // have 100 elements, remove 100 elements
    for (int i = 1; i < 101 + REBAL; i++) {
      assertEquals(i*10, (int)ihm.remove(i + 100));
    }
   
    assertEquals(64, ihm.getCapacity());
    
  }
  
  public void testRandom() {
    int countAdd = 0;
    int dupsA = 0;
    int notPres = 0;
    int countRmv = 0;
    
    long seed = // -6616473831883690L;
        new Random().nextLong();
    System.out.println("Random seed for Int2ObjHashMapTest: " + seed);
    Random r = new Random(seed);
    
    for (int i = 1; i < 1024 * 512; i++) {
      int k = i & 1024 - 1;
      if (k == 0) continue;
      if (r.nextInt(3) > 0) {
        int sz = ihm.size();
        if (ihm.put(k, -k) == null) {
          countAdd ++;
          assertEquals(sz + 1, ihm.size());
        } else {
          dupsA++;
        }
      } else {
        int sz = ihm.size();
        if (ihm.remove(k) != null) {
          countRmv ++;
          assertEquals(sz - 1, ihm.size());
        } else {
          notPres++;
        }
        
      }
    }
    System.out.format("%s testRandom added: %,d dups: %,d rmvd: %,d notPres: %,d, size: %d%n",         
        this.getClass().getName(), countAdd, dupsA, countRmv, notPres, ihm.size());
    assertEquals(countAdd - countRmv, ihm.size() );
  }
}