From 53e2adff5e923acc2cd7aaa074f4f3a9372f77ce Mon Sep 17 00:00:00 2001
From: ribeaudc <ribeaudc>
Date: Wed, 5 Sep 2007 14:52:05 +0000
Subject: [PATCH] add: - CollectionUtils class and its unit test.
SVN: 1622
---
.../common/utilities/CollectionUtils.java | 158 ++++++++++++++++++
.../common/utilities/CollectionUtilsTest.java | 65 +++++++
2 files changed, 223 insertions(+)
create mode 100644 common/source/java/ch/systemsx/cisd/common/utilities/CollectionUtils.java
create mode 100644 common/sourceTest/java/ch/systemsx/cisd/common/utilities/CollectionUtilsTest.java
diff --git a/common/source/java/ch/systemsx/cisd/common/utilities/CollectionUtils.java b/common/source/java/ch/systemsx/cisd/common/utilities/CollectionUtils.java
new file mode 100644
index 00000000000..a9617a1ee97
--- /dev/null
+++ b/common/source/java/ch/systemsx/cisd/common/utilities/CollectionUtils.java
@@ -0,0 +1,158 @@
+/*
+ * Copyright 2007 ETH Zuerich, CISD
+ *
+ * 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 ch.systemsx.cisd.common.utilities;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Iterator;
+
+/**
+ * Some convenience methods/utilities around {@link Collection}.
+ *
+ * @author Christian Ribeaud
+ */
+public final class CollectionUtils
+{
+
+ public final static String DEFAULT_COLLECTION_START = "[";
+
+ public final static String DEFAULT_COLLECTION_END = "]";
+
+ public final static String DEFAULT_COLLECTION_SEPARATOR = ", ";
+
+ private static String collectionStart = DEFAULT_COLLECTION_START;
+
+ private static String collectionEnd = DEFAULT_COLLECTION_END;
+
+ private static String collectionSeparator = DEFAULT_COLLECTION_SEPARATOR;
+
+ private CollectionUtils()
+ {
+ // Can not be instantiated
+ }
+
+ public static final void setCollectionEnd(String collectionEnd)
+ {
+ CollectionUtils.collectionEnd = collectionEnd;
+ }
+
+ public static final void setCollectionSeparator(String collectionSeparator)
+ {
+ CollectionUtils.collectionSeparator = collectionSeparator;
+ }
+
+ public static final void setCollectionStart(String collectionStart)
+ {
+ CollectionUtils.collectionStart = collectionStart;
+ }
+
+ public static final String getCollectionEnd()
+ {
+ return collectionEnd;
+ }
+
+ public static final String getCollectionSeparator()
+ {
+ return collectionSeparator;
+ }
+
+ public static final String getCollectionStart()
+ {
+ return collectionStart;
+ }
+
+ /**
+ * Abbreviates a given array of <code>Object</code> using ellipses.
+ * <p>
+ * By default it shows the number of items left.
+ * </p>
+ *
+ * @param maxLength the maximum number of items that should be shown. If <code>-1</code> then all items will be
+ * displayed.
+ */
+ public final static String abbreviate(Object[] objects, int maxLength)
+ {
+ return abbreviate(objects, maxLength, true);
+ }
+
+ /**
+ * Abbreviates a given <code>Collection</code> using ellipses.
+ * <p>
+ * By default it shows the number of items left.
+ * </p>
+ *
+ * @param maxLength the maximum number of items that should be shown. If <code>-1</code> then all items will be
+ * displayed.
+ */
+ public final static String abbreviate(Collection<?> collection, int maxLength)
+ {
+ return abbreviate(collection, maxLength, true);
+ }
+
+ /**
+ * Abbreviates a given array of <code>Object</code> using ellipses.
+ *
+ * <pre>
+ * CollectionUtils.abbreviate(new String[] { "1", "2", "3", "4", "5" }, 3, false) = "[1, 2, 3, ...]"
+ * CollectionUtils.abbreviate(new String[] { "1", "2", "3", "4", "5" }, 3, true) = "[1, 2, 3, ... (2 left)]"
+ * </pre>
+ *
+ * @param maxLength the maximum number of items that should be shown. If <code>-1</code> then all items will be
+ * displayed.
+ * @param showLeft whether the number of items left should be displayed at the end of the output. This is only
+ * relevant if you limit the number of items displayed.
+ */
+ public final static String abbreviate(Object[] objects, int maxLength, boolean showLeft)
+ {
+ return abbreviate(Arrays.asList(objects), maxLength, showLeft);
+ }
+
+ /**
+ * Abbreviates a given <code>Collection</code> using ellipses.
+ *
+ * @param maxLength the maximum number of items that should be shown. If <code>-1</code> then all items will be
+ * displayed.
+ * @param showLeft whether the number of items left should be displayed at the end of the output. This is only
+ * relevant if you limit the number of items displayed.
+ */
+ public final static String abbreviate(Collection<?> collection, int maxLength, boolean showLeft)
+ {
+ assert collection != null;
+ StringBuilder builder = new StringBuilder(collectionStart);
+ Iterator<?> iterator = collection.iterator();
+ for (int i = 0; iterator.hasNext() && (i < maxLength || maxLength < 0); i++)
+ {
+ if (i > 0)
+ {
+ builder.append(collectionSeparator);
+ }
+ builder.append(String.valueOf(iterator.next()));
+ }
+ int size = collection.size();
+ if (maxLength > 0 && maxLength < size)
+ {
+ builder.append(collectionSeparator);
+ builder.append("...");
+ if (showLeft)
+ {
+ builder.append(" (").append(size - maxLength).append(" left)");
+ }
+ }
+ builder.append(collectionEnd);
+ return builder.toString();
+ }
+}
\ No newline at end of file
diff --git a/common/sourceTest/java/ch/systemsx/cisd/common/utilities/CollectionUtilsTest.java b/common/sourceTest/java/ch/systemsx/cisd/common/utilities/CollectionUtilsTest.java
new file mode 100644
index 00000000000..f24736f4f83
--- /dev/null
+++ b/common/sourceTest/java/ch/systemsx/cisd/common/utilities/CollectionUtilsTest.java
@@ -0,0 +1,65 @@
+/*
+ * Copyright 2007 ETH Zuerich, CISD
+ *
+ * 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 ch.systemsx.cisd.common.utilities;
+
+import static org.testng.AssertJUnit.*;
+
+import java.util.Collection;
+
+import org.apache.commons.lang.StringUtils;
+import org.testng.annotations.Test;
+
+/**
+ * Test cases for the {@link CollectionUtils} class.
+ *
+ * @author Christian Ribeaud
+ */
+public final class CollectionUtilsTest
+{
+
+ @Test
+ public final void testAbbreviateWithArray()
+ {
+ try
+ {
+ CollectionUtils.abbreviate((Collection<?>) null, 0, false);
+ fail("Given list can not be null.");
+ } catch (AssertionError e)
+ {
+ // Nothing to do here
+ }
+ String[] s = StringUtilities.getStrings(5);
+ String string =
+ CollectionUtils.getCollectionStart() + StringUtils.join(s, CollectionUtils.getCollectionSeparator())
+ + CollectionUtils.getCollectionEnd();
+ assertEquals(string, CollectionUtils.abbreviate(s, -1, false));
+ assertEquals(string, CollectionUtils.abbreviate(s, -10, false));
+ assertEquals(string, CollectionUtils.abbreviate(s, 5, false));
+ assertEquals(string, CollectionUtils.abbreviate(s, 10, false));
+ // With ellipses
+ s = new String[]
+ { "1", "2", "3", "4", "5" };
+ assertEquals("[1, 2, 3, ...]", CollectionUtils.abbreviate(s, 3, false));
+ assertEquals("[1, ...]", CollectionUtils.abbreviate(s, 1, false));
+ assertEquals("[]", CollectionUtils.abbreviate(s, 0, false));
+ // With show left
+ assertEquals("[]", CollectionUtils.abbreviate(s, 0));
+ assertEquals("[1, ... (4 left)]", CollectionUtils.abbreviate(s, 1));
+ assertEquals("[1, 2, ... (3 left)]", CollectionUtils.abbreviate(s, 2));
+ assertEquals(CollectionUtils.abbreviate(s, 10, false), CollectionUtils.abbreviate(s, 10));
+ }
+}
--
GitLab