Author: bayard
Date: Thu Jan 21 08:38:12 2010
New Revision: 901595
URL: http://svn.apache.org/viewvc?rev=901595&view=rev
Log:
Applying Srihari Reddy's patch from LANG-405, based on Dave Meikle's original
patch. This adds a truncateMiddle method to StringUtils.
Modified:
commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/StringUtils.java
commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/StringUtilsTest.java
Modified:
commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/StringUtils.java
URL:
http://svn.apache.org/viewvc/commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/StringUtils.java?rev=901595&r1=901594&r2=901595&view=diff
==============================================================================
---
commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/StringUtils.java
(original)
+++
commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/StringUtils.java
Thu Jan 21 08:38:12 2010
@@ -6052,4 +6052,53 @@
int strOffset = str.length() - suffix.length();
return str.regionMatches(ignoreCase, strOffset, suffix, 0,
suffix.length());
}
+
+ /**
+ * <p>Truncates a String to the length passed, replacing the middle
characters with the supplied
+ * replacement String.</p>
+ *
+ * <p>This truncation only occurs if the following criteria is met:
+ * <ul>
+ * <li>Neither the String for truncation nor the replacement String are
null or empty </li>
+ * <li>The length to truncate to is less than the length of the supplied
String</li>
+ * <li>The length to truncate to is greater than 0</li>
+ * <li>The truncated String will have enough room for the length supplied
replacement String
+ * and the first and last characters of the supplied String for
truncation</li>
+ * </ul>
+ * Otherwise, the returned String will be the same as the supplied String
for truncation.
+ * </p>
+ *
+ * <pre>
+ * StringUtils.truncateMiddle(null, null, 0) = null
+ * StringUtils.truncateMiddle("abc", null, 0) = "abc"
+ * StringUtils.truncateMiddle("abc", ".", 0) = "abc"
+ * StringUtils.truncateMiddle("abc", ".", 3) = "abc"
+ * StringUtils.truncateMiddle("abcdef", ".", 4) = "ab.f"
+ * </pre>
+ *
+ * @param str the String to truncate, may be null
+ * @param middle the String to replace the middle characters with, may be
null
+ * @param length the length to truncate <code>str</code> to.
+ * @return the truncated String if the above criteria is met, or the
original String supplied for truncation.
+ */
+ public static String truncateMiddle(String str, String middle, int length)
{
+ if (isEmpty(str) || isEmpty(middle)) {
+ return str;
+ }
+
+ if (length >= str.length() || length < (middle.length()+2)) {
+ return str;
+ }
+
+ int targetSting = length-middle.length();
+ int startOffset = targetSting/2+targetSting%2;
+ int endOffset = str.length()-targetSting/2;
+
+ StringBuilder builder = new StringBuilder(length);
+ builder.append(str.substring(0,startOffset));
+ builder.append(middle);
+ builder.append(str.substring(endOffset));
+
+ return builder.toString();
+ }
}
Modified:
commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/StringUtilsTest.java
URL:
http://svn.apache.org/viewvc/commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/StringUtilsTest.java?rev=901595&r1=901594&r2=901595&view=diff
==============================================================================
---
commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/StringUtilsTest.java
(original)
+++
commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/StringUtilsTest.java
Thu Jan 21 08:38:12 2010
@@ -1686,6 +1686,45 @@
assertEquals("queued", StringUtils.remove("queued", 'z'));
}
+ public void testTruncateMiddle() {
+ // javadoc examples
+ assertNull( StringUtils.truncateMiddle(null, null, 0) );
+ assertEquals( "abc", StringUtils.truncateMiddle("abc", null, 0) );
+ assertEquals( "abc", StringUtils.truncateMiddle("abc", ".", 0) );
+ assertEquals( "abc", StringUtils.truncateMiddle("abc", ".", 3) );
+ assertEquals( "ab.f", StringUtils.truncateMiddle("abcdef", ".", 4) );
+
+ // JIRA issue (LANG-405) example (slightly different than actual
expected result)
+ assertEquals(
+ "A very long text with un...f the text is complete.",
+ StringUtils.truncateMiddle(
+ "A very long text with unimportant stuff in the middle but
interesting start and " +
+ "end to see if the text is complete.", "...", 50) );
+
+ // Test a much longer text :)
+ String longText = "Start text" + StringUtils.repeat("x", 10000) +
"Close text";
+ assertEquals(
+ "Start text->Close text",
+ StringUtils.truncateMiddle( longText, "->", 22 ) );
+
+ // Test negative length
+ assertEquals("abc", StringUtils.truncateMiddle("abc", ".", -1));
+
+ // Test boundaries
+ // Fails to change anything as method ensures first and last char are
kept
+ assertEquals("abc", StringUtils.truncateMiddle("abc", ".", 1));
+ assertEquals("abc", StringUtils.truncateMiddle("abc", ".", 2));
+
+ // Test length of n=1
+ assertEquals("a", StringUtils.truncateMiddle("a", ".", 1));
+
+ // Test smallest length that can lead to success
+ assertEquals("a.d", StringUtils.truncateMiddle("abcd", ".", 3));
+
+ // More from LANG-405
+ assertEquals("a..f", StringUtils.truncateMiddle("abcdef", "..", 4));
+ assertEquals("ab.ef", StringUtils.truncateMiddle("abcdef", ".", 5));
+ }
public void testDifferenceAt_StringArray(){
assertEquals(-1, StringUtils.indexOfDifference(null));
