CoreMatchers.java

package com.levelup.java.hamcrest;

import static org.hamcrest.CoreMatchers.allOf;
import static org.hamcrest.CoreMatchers.anyOf;
import static org.hamcrest.CoreMatchers.anything;
import static org.hamcrest.CoreMatchers.both;
import static org.hamcrest.CoreMatchers.containsString;
import static org.hamcrest.CoreMatchers.describedAs;
import static org.hamcrest.CoreMatchers.endsWith;
import static org.hamcrest.CoreMatchers.equalTo;
import static org.hamcrest.CoreMatchers.everyItem;
import static org.hamcrest.CoreMatchers.hasItems;
import static org.hamcrest.CoreMatchers.instanceOf;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.isA;
import static org.hamcrest.CoreMatchers.notNullValue;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.hamcrest.CoreMatchers.startsWith;
import static org.hamcrest.number.OrderingComparison.greaterThanOrEqualTo;
import static org.junit.Assert.assertThat;

import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.hamcrest.core.IsSame;
import org.junit.Test;

import com.google.common.collect.Lists;

/**
 * This java example will demonstrate hamcrest
 * core matchers.
 * 
 * @author Justin Musgrove
 * @see <a href='http://www.leveluplunch.com/java/examples/hamcrest-core-matchers-junit-testing/'>Core matchers</a>
 * 
 */
public class CoreMatchers {
	
	@Test
	public void hamcrest_core_allof () {

		String microBrew = "Lake Louie Brewery Company";
		
		assertThat(microBrew, allOf(startsWith("Lake"), containsString("Brew")));
	}
	
	@Test
	public void hamcrest_core_anyOf () {
		
		String microBrew = "Grumpy Troll Brewery";
		
		assertThat(microBrew, anyOf(startsWith("brew"), containsString("Troll")));
	}

	@Test
	public void hamcrest_core_combinableMatcher () {
		
		String isLite = "Miller Lite";
		
		assertThat(isLite, both(containsString("Miller")).and(containsString("Lite")));
	}

	@Test
	public void hamcrest_core_describedAs () {
		
		BigDecimal myBigDecimal = new BigDecimal("0");
		
		assertThat(myBigDecimal, 
				describedAs("a big decimal equal to %0", 
						equalTo(myBigDecimal), 
						myBigDecimal.toPlainString()));
	}

	
	@Test
	public void hamcrest_core_every () {
		
		List<Integer> ages = Lists.newArrayList(21, 25, 30, 18);
		assertThat(ages, everyItem(greaterThanOrEqualTo(18)));
	}
	
	
	@Test
	public void hamcrest_core_is() {
		
		String isLite = "Miller Brewing Company";
		
		assertThat("Miller Brewing Company", is(equalTo(isLite)));
	}
			
	@Test
	public void hamcrest_core_isA() {
		
		Map<Integer, String> map = new HashMap<Integer, String>();
		
		assertThat(map, isA(Map.class));
	}
	
	
	@Test
	public void hamcrest_core_anything () {
		
		assertThat("", anything());
	}
	

	@Test
	@SuppressWarnings("unchecked")
	public void hamcrest_core_hasItems_matchers () {
		
		List<String> regionalBreweries = Lists.newArrayList(
				"Capital Brewery", 
				"City Brewing Company ", 
				"Jacob Leinenkugel Brewing Company",
				"Lakefront Brewery", 
				"New Glarus Brewing Company", 
				"Stevens Point Brewery"); 
		
		assertThat(regionalBreweries, hasItems(
				containsString("Brew"), 
				endsWith("y")));
	}
	
	@Test
	public void hamcrest_core_hasItems () {
		
		List<String> regionalBreweries = Lists.newArrayList(
				"Capital Brewery", 
				"City Brewing Company ", 
				"Jacob Leinenkugel Brewing Company",
				"Lakefront Brewery, Inc.", 
				"New Glarus Brewing Company", 
				"Stevens Point Brewery"); 
		
		assertThat(regionalBreweries, hasItems(
				"Capital Brewery", 
				"City Brewing Company ", 
				"Jacob Leinenkugel Brewing Company",
				"Lakefront Brewery, Inc.", 
				"New Glarus Brewing Company", 
				"Stevens Point Brewery"));
	}
	
	@Test
	public void hamcrest_core_isEqual () {
		
		String spottedCreator = "New Glarus Brewing Company";
		
		assertThat(spottedCreator, equalTo("New Glarus Brewing Company"));
	}
	
	
	@Test
	public void hamcrest_core_isInstanceOf () {

		Calendar cal = Calendar.getInstance();
		
		assertThat(cal, instanceOf(Calendar.class));
	}
	
	@Test
	public void hamcrest_core_is_notNullValue () {

		Set<String> daNull = new HashSet<String>();
		
		assertThat(daNull, is(notNullValue()));
	}
	
	
	@Test
	public void hamcrest_core_is_nullValue () {
		
		Set<String> daNull = null;
		
		assertThat(daNull, is(nullValue()));
	}
	
	@Test
	public void hamcrest_core_isSame_string () {
		
		String wiBrewery = "Capital Brewery";
		String wiRegionalBrewery = "Capital Brewery";
		
		assertThat(wiRegionalBrewery, IsSame.<String>sameInstance(wiBrewery));
	}
	
	@Test
	public void hamcrest_core_is_same_list () {
				
		List<String> someList = new ArrayList<String>();
		
		assertThat(someList, IsSame.<List<String>>sameInstance(someList));
	}

	@Test
	public void hamcrest_core_containsString () {
		
		String brewery = "Pabst Brewing Company";
		
		assertThat(brewery, containsString("Brew"));
	}
	
	
	@Test
	public void hamcrest_core_string_startsWith () {

		String highSchool = "Tarpon spring spongers";
		
		assertThat(highSchool, startsWith("Tarpon"));
	}
	
	@Test
	public void hamcrest_core_string_endsWith () {
		
		String baseBallTeam = "Milwaukee brewers";
		
		assertThat(baseBallTeam, endsWith("brewers"));
	}
	
	

}