/*
    * Copyright 2007 Kasper B. Graversen
    * 
    * 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 org.supercsv.util;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertTrue;
  
  import java.lang.reflect.Method;
  
  import org.junit.After;
  import org.junit.Before;
  import org.junit.Test;
  import org.supercsv.mock.ReflectionBean;
  
  /**
   * Tests the MethodCache class.
   * 
   * @author James Bassett
   */
  public class MethodCacheTest {
  	
  	private MethodCache cache;
  	
  	/**
  	 * Sets up before the test.
  	 */
  	@Before
  	public void setUp() {
  		cache = new MethodCache();
  	}
  	
  	/**
  	 * Tidies up after the test.
  	 */
  	@After
  	public void tearDown() {
  		cache = null;
  	}
  	
  	/**
  	 * Tests getGetMethod().
  	 */
  	@Test
  	public void testGetGetMethod() throws Exception {
  		ReflectionBean bean = new ReflectionBean();
  		
  		// first time - not cached
  		final long start = System.currentTimeMillis();
  		final Method uncachedGetter = cache.getGetMethod(bean, "name");
  		final long uncachedTime = System.currentTimeMillis() - start;
  		
  		// second time - cached
  		final long start2 = System.currentTimeMillis();
  		final Method cachedGetter = cache.getGetMethod(bean, "name");
  		final long cachedTime = System.currentTimeMillis() - start2;
  		
  		// retrieval from cache should be at least as fast as reflection
  		System.out.println(String.format("getGetMethod uncachedTime: %d, cachedTime: %d", uncachedTime, cachedTime));
  		assertTrue(cachedTime <= uncachedTime);
  		
  		// the same getter method should be returned in both calls
  		assertEquals(uncachedGetter, cachedGetter);
  		
  		// test the uncached getter works
  		final String name1 = "uncached";
  		bean.setName(name1);
  		assertEquals(name1, uncachedGetter.invoke(bean));
  		
  		// test the cached getter works
  		final String name2 = "cached";
  		bean.setName(name2);
  		assertEquals(name2, cachedGetter.invoke(bean));
  	}
  	
  	/**
  	 * Tests getSetMethod().
  	 */
  	@Test
  	public void testGetSetMethod() throws Exception {
  		ReflectionBean bean = new ReflectionBean();
  		
  		// first time - not cached
  		final long start = System.currentTimeMillis();
  		final Method uncachedSetter = cache.getSetMethod(bean, "name", String.class);
  		final long uncachedTime = System.currentTimeMillis() - start;
  		
 		// second time - cached
 		final long start2 = System.currentTimeMillis();
 		final Method cachedSetter = cache.getSetMethod(bean, "name", String.class);
 		final long cachedTime = System.currentTimeMillis() - start2;
 		
 		// retrieval from cache should be at least as fast as reflection
 		System.out.println(String.format("getSetMethod uncachedTime: %d, cachedTime: %d", uncachedTime, cachedTime));
 		assertTrue(cachedTime <= uncachedTime);
 		
 		// the same setter method should be returned in both calls
 		assertEquals(uncachedSetter, cachedSetter);
 		
 		// test the uncached setter works
 		final String name1 = "uncached";
 		uncachedSetter.invoke(bean, name1);
 		assertEquals(name1, bean.getName());
 		
 		// test the cached setter works
 		final String name2 = "cached";
 		cachedSetter.invoke(bean, name2);
 		assertEquals(name2, bean.getName());
 	}
 	
 	/**
 	 * Tests getGetMethod() with a null object (should throw an exception).
 	 */
 	@Test(expected = NullPointerException.class)
 	public void testGetGetMethodWithNullObject() {
 		cache.getGetMethod(null, "name");
 	}
 	
 	/**
 	 * Tests getGetMethod() with a null field name (should throw an exception).
 	 */
 	@Test(expected = NullPointerException.class)
 	public void testGetGetMethodWithNullFieldName() {
 		cache.getGetMethod(new ReflectionBean(), null);
 	}
 	
 	/**
 	 * Tests getSetMethod() with a null object (should throw an exception).
 	 */
 	@Test(expected = NullPointerException.class)
 	public void testGetSetMethodWithNullObject() {
 		cache.getSetMethod(null, "name", String.class);
 	}
 	
 	/**
 	 * Tests getSetMethod() with a null field name (should throw an exception).
 	 */
 	@Test(expected = NullPointerException.class)
 	public void testGetSetMethodWithNullFieldName() {
 		cache.getSetMethod(new ReflectionBean(), null, String.class);
 	}
 	
 	/**
 	 * Tests getSetMethod() with a null argument type (should throw an exception).
 	 */
 	@Test(expected = NullPointerException.class)
 	public void testGetSetMethodWithNullArgumentType() {
 		cache.getSetMethod(new ReflectionBean(), "name", null);
 	}
 	
 }