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Merge branch 'LANG-1411'

This commit is contained in:
Benedikt Ritter 2018-08-20 18:59:21 +02:00
parent c2bd8be862 2a11642511
commit 44e32205a6
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2 changed files with 121 additions and 0 deletions
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74
src/main/java/org/apache/commons/lang3/ObjectUtils.java
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@ -21,6 +21,7 @@ import java.io.Serializable;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
@ -77,6 +78,79 @@ public class ObjectUtils {
super();
}
// Empty checks
//-----------------------------------------------------------------------
/**
* <p>Checks if an Object is empty or null.</p>
*
* The following types are supported:
* <ul>
* <li>{@link CharSequence}: Considered empty if its length is zero.</li>
* <li>{@code Array}: Considered empty if its length is zero.</li>
* <li>{@link Collection}: Considered empty if it has zero elements.</li>
* <li>{@link Map}: Considered empty if it has zero key-value mappings.</li>
* </ul>
*
* <pre>
* ObjectUtils.isEmpty(null) = true
* ObjectUtils.isEmpty("") = true
* ObjectUtils.isEmpty("ab") = false
* ObjectUtils.isEmpty(new int[]{}) = true
* ObjectUtils.isEmpty(new int[]{1,2,3}) = false
* ObjectUtils.isEmpty(1234) = false
* </pre>
*
* @param object the {@code Object} to test, may be {@code null}
* @return {@code true} if the object has a supported type and is empty or null,
* {@code false} otherwise
*/
public static boolean isEmpty(final Object object) {
if (object == null) {
return true;
}
if (object instanceof CharSequence) {
return ((CharSequence) object).length() == 0;
}
if (object.getClass().isArray()) {
return Array.getLength(object) == 0;
}
if (object instanceof Collection<?>) {
return ((Collection<?>) object).isEmpty();
}
if (object instanceof Map<?, ?>) {
return ((Map<?, ?>) object).isEmpty();
}
return false;
}
/**
* <p>Checks if an Object is not empty and not null.</p>
*
* The following types are supported:
* <ul>
* <li>{@link CharSequence}: Considered empty if its length is zero.</li>
* <li>{@code Array}: Considered empty if its length is zero.</li>
* <li>{@link Collection}: Considered empty if it has zero elements.</li>
* <li>{@link Map}: Considered empty if it has zero key-value mappings.</li>
* </ul>
*
* <pre>
* ObjectUtils.isNotEmpty(null) = false
* ObjectUtils.isNotEmpty("") = false
* ObjectUtils.isNotEmpty("ab") = true
* ObjectUtils.isNotEmpty(new int[]{}) = false
* ObjectUtils.isNotEmpty(new int[]{1,2,3}) = true
* ObjectUtils.isNotEmpty(1234) = true
* </pre>
*
* @param object the {@code Object} to test, may be {@code null}
* @return {@code true} if the object has an unsupported type or is not empty
* and not null, {@code false} otherwise
*/
public static boolean isNotEmpty(final Object object) {
return !isEmpty(object);
}
// Defaulting
//-----------------------------------------------------------------------
/**

47
src/test/java/org/apache/commons/lang3/ObjectUtilsTest.java
View File

@ -31,9 +31,14 @@ import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Calendar;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.commons.lang3.exception.CloneFailedException;
import org.apache.commons.lang3.mutable.MutableObject;
@ -47,6 +52,13 @@ import org.junit.Test;
public class ObjectUtilsTest {
private static final String FOO = "foo";
private static final String BAR = "bar";
private static final String[] NON_EMPTY_ARRAY = new String[] { FOO, BAR, };
private static final List<String> NON_EMPTY_LIST = Arrays.asList(NON_EMPTY_ARRAY);
private static final Set<String> NON_EMPTY_SET = new HashSet<>(NON_EMPTY_LIST);
private static final Map<String, String> NON_EMPTY_MAP = new HashMap<>();
static {
NON_EMPTY_MAP.put(FOO, BAR);
}
//-----------------------------------------------------------------------
@Test
@ -59,6 +71,41 @@ public class ObjectUtilsTest {
assertFalse(Modifier.isFinal(ObjectUtils.class.getModifiers()));
}
//-----------------------------------------------------------------------
@Test
public void testIsEmpty() {
assertTrue(ObjectUtils.isEmpty(null));
assertTrue(ObjectUtils.isEmpty(""));
assertTrue(ObjectUtils.isEmpty(new int[] {}));
assertTrue(ObjectUtils.isEmpty(Collections.emptyList()));
assertTrue(ObjectUtils.isEmpty(Collections.emptySet()));
assertTrue(ObjectUtils.isEmpty(Collections.emptyMap()));
assertFalse(ObjectUtils.isEmpty(" "));
assertFalse(ObjectUtils.isEmpty("ab"));
assertFalse(ObjectUtils.isEmpty(NON_EMPTY_ARRAY));
assertFalse(ObjectUtils.isEmpty(NON_EMPTY_LIST));
assertFalse(ObjectUtils.isEmpty(NON_EMPTY_SET));
assertFalse(ObjectUtils.isEmpty(NON_EMPTY_MAP));
}
@Test
public void testIsNotEmpty() {
assertFalse(ObjectUtils.isNotEmpty(null));
assertFalse(ObjectUtils.isNotEmpty(""));
assertFalse(ObjectUtils.isNotEmpty(new int[] {}));
assertFalse(ObjectUtils.isNotEmpty(Collections.emptyList()));
assertFalse(ObjectUtils.isNotEmpty(Collections.emptySet()));
assertFalse(ObjectUtils.isNotEmpty(Collections.emptyMap()));
assertTrue(ObjectUtils.isNotEmpty(" "));
assertTrue(ObjectUtils.isNotEmpty("ab"));
assertTrue(ObjectUtils.isNotEmpty(NON_EMPTY_ARRAY));
assertTrue(ObjectUtils.isNotEmpty(NON_EMPTY_LIST));
assertTrue(ObjectUtils.isNotEmpty(NON_EMPTY_SET));
assertTrue(ObjectUtils.isNotEmpty(NON_EMPTY_MAP));
}
//-----------------------------------------------------------------------
@Test
public void testIsNull() {