*/
    @Test
    public void testGet() throws Exception {
        assertThat(map.get("1"), is("test"));
        assertThat(map.get(null), is(nullValue()));
        assertThat(map.get("test3"), is(nullValue()));
        assertThat(map.getAt(0), is(nullValue()));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testPut() throws Exception {

        list.addLast(null);
        list.addLast("1");
        list.addLast("2");
        list.clear();
        assertThat(list.size(), is(0));
        assertThat(list.getFirstEntry(), is(nullValue()));
        assertThat(list.getLastEntry(), is(nullValue()));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testGetEntry() throws Exception {
        list.addLast("1");
        list.addLast("2");

     */
    @Test
    public void testToDate_Null() throws Exception {
        assertThat(toDate(null), is(nullValue()));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testToDate_EmptyString() throws Exception {
        assertThat(toDate(""), is(nullValue()));
    }

    /**
     * @throws Exception
     */
    @Test

    //    public void testToDate_Null() throws Exception {
    //        assertThat(toDate(null, Locale.JAPAN), is(nullValue()));
    //    }

    /**
     * @throws Exception
     */
    @Test
    public void testToDate_EmptyString() throws Exception {
        assertThat(toDate("", Locale.JAPAN), is(nullValue()));
    }

    /**
     * @throws Exception
     */
    @Test

 * governing permissions and limitations under the License.
 */
package org.codelibs.core.lang;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.assertTrue;

 */
package org.codelibs.core.collection;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.not;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.junit.Assert.assertThat;

import java.util.HashMap;
import java.util.Map;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;

/**
 * @author higa
 */

 * governing permissions and limitations under the License.
 */
package org.codelibs.core.lang;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.junit.Assert.assertThat;

import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.util.Map;

import org.junit.Test;

/**
 * @author higa
 */

 * governing permissions and limitations under the License.
 */
package org.codelibs.core.convert;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.junit.Assert.assertThat;

import org.codelibs.core.exception.ClIllegalArgumentException;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.ExpectedException;

/**

 */
package org.codelibs.core.beans.impl;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.notNullValue;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.hamcrest.CoreMatchers.sameInstance;
import static org.junit.Assert.assertThat;

import java.lang.reflect.Constructor;

import org.codelibs.core.beans.BeanDesc;

        assertEquals("present", presentOptional.get());
        assertEquals("present", presentOptional.orElse("default"));

        // Test with null value
        String nullValue = null;
        OptionalEntity<String> emptyOptional = OptionalUtil.ofNullable(nullValue);

        assertFalse(emptyOptional.isPresent());
        assertEquals("default", emptyOptional.orElse("default"));