update: commons-lang 2.4 now includes an intelligent abbreviation method . So no need to duplicate this anymore.

It happens so often that I'm in the need for some small utility methods. Most of the time the needed code can be found in commons lang or the various spring util classes. But sometimes both don't give an answer. That is the time for my all time favourite util classes (duplicated in every project ;-)) - named FooBarUtils.

Today I was working on kinokai.de and was in desperate need for the following functionality:

• remove all html tags from a string
• do intelligent abbreviation of a string (do no cut in the middle of words)

See the following code snippets for my KkStringUtils - maybe you need similar functionality in one of your projects and can reuse my code. Note that the class contains some other String related functionality... package de.kinokai.util; import java.io.IOException; import java.io.Reader; import java.io.StringReader; import javax.swing.text.html.HTMLEditorKit; import javax.swing.text.html.parser.ParserDelegator; import org.apache.commons.lang.StringUtils; /** * Generic String manipulation functions that are not available in Commons Lang * or Spring String Utils * * @author Kai Grabfelder (kai.grabfelder@kinokai.de) * */ public class KkStringUtils { /** * joins the given strings * * @param strings * the varargs strings (may be null) * * @return the joined string, may be empty, but never null */ public static String join(String... strings) { if (strings == null || strings.length == 0) return ""; StringBuilder sw = new StringBuilder(); for (String string : strings) { if (string == null) continue; sw.append(string); } return sw.toString(); } /** * checks if all otherStrings are equal with compareString * * @return true if all strings are equal */ public final static boolean equals(String compareString, String... otherStrings) { for (String string : otherStrings) { boolean equals = org.apache.commons.lang.StringUtils.equals(compareString, string); if (equals == false) return false; } return true; } /** * abbreviates a given input string to a given length. As long as it is * possible the abbreviation will be done at blanks or words. * * @param input * the string that should be abbreviated * * @param length * the max length of the * * @return the abbreviated string or null */ public final static String abbreviate(String input, int length) { if (input == null) return null; int stringLength = input.length(); // no need for abbreviation if (stringLength <= length) return input; // if the string is too short return the substring if (length < 3) return input.substring(0, length); String result = input.substring(0, length - 3); int lastSeparator = StringUtils.lastIndexOfAny(result, new String[] { " ", "-" }); if (lastSeparator > 0) { result = result.substring(0, lastSeparator); } return result + "..."; } /** * checks if at least one of otherStrings is equal with compareString * * @return true if at least one of otherStrings is equal with compareString * false otherwhise */ public final static boolean equalsWithOne(String compareString, String... otherStrings) { for (String string : otherStrings) { boolean equals = org.apache.commons.lang.StringUtils.equals(compareString, string); if (equals == true) return true; } return false; } /** * removes all html tags from the given input string * * @param input * the string to remove tags from * * @return input without any html tags, or null if input was null */ public final static String stripHTMLTags(String input) { if (input == null) return null; HtmlParserCallback parser = new HtmlParserCallback(); StringReader sr = new StringReader(input); try { parser.parse(sr); } catch (IOException e) { throw new RuntimeException( "error stripping tags from input: " + input + "error message: " + e.getMessage(), e); } sr.close(); return parser.getText(); } private static class HtmlParserCallback extends HTMLEditorKit.ParserCallback { private StringBuilder s; public HtmlParserCallback() { } public void parse(Reader in) throws IOException { s = new StringBuilder(); ParserDelegator delegator = new ParserDelegator(); delegator.parse(in, this, Boolean.TRUE); } @Override public void handleText(char[] text, int pos) { s.append(text); } public String getText() { return s.toString(); } } } And a really small unit test: package de.kinokai.util; import junit.framework.TestCase; public class KkStringUtilsTest extends TestCase { public void testJoin() { String join = KkStringUtils.join("A"); assertEquals("A", join); join = KkStringUtils.join("A", "B"); assertEquals("AB", join); join = KkStringUtils.join("A", ", ", "B"); assertEquals("A, B", join); join = KkStringUtils.join("A", ", ", "B", null); assertEquals("A, B", join); join = KkStringUtils.join((String) null); assertEquals("", join); join = KkStringUtils.join((String[]) null); assertEquals("", join); } public void testStripHTMLTags() { String string = KkStringUtils.stripHTMLTags("<a href='asdf'>foobar</a>"); assertEquals("foobar", string); string = KkStringUtils.stripHTMLTags("<a href='asdf'>foobar"); assertEquals("foobar", string); string = KkStringUtils.stripHTMLTags("< asdf"); assertEquals("asdf", string); string = KkStringUtils.stripHTMLTags(null); assertEquals(null, string); } public void testAbbreviate() { String string = KkStringUtils.abbreviate("aabbcc ddeeffgghhiijjkk", 15); assertEquals("aabbcc...", string); assertNull(KkStringUtils.abbreviate(null, 0)); string = KkStringUtils.abbreviate("aabbcc ddeeffgghhiijjkk", 0); assertEquals("", string); string = KkStringUtils.abbreviate("aabbcc ddeeffgghhiijjkk", 99990); assertEquals("aabbcc ddeeffgghhiijjkk", string); string = KkStringUtils.abbreviate("aabbccddeeffgghhiijjkk", 10); assertEquals("aabbccd...", string); string = KkStringUtils.abbreviate("aabbccddeeffgghhiijjkk", 2); assertEquals("aa", string); } }