svn commit: r1597502 - /logging/log4j/log4j2/trunk/log4j-api/src/main/java/org/apache/logging/log4j/util/Strings.java

[mattsicker]

Author: mattsicker
Date: Mon May 26 02:34:51 2014
New Revision: 1597502

URL: http://svn.apache.org/r1597502
Log:
Add trimToNull to Strings utility class.

  - Made class final.
  - Added private constructor.
  - Fixed javadoc to refer to correct class.
  - Removed @since tags from javadoc (wrong version references).

Modified:
    
logging/log4j/log4j2/trunk/log4j-api/src/main/java/org/apache/logging/log4j/util/Strings.java

Modified: 
logging/log4j/log4j2/trunk/log4j-api/src/main/java/org/apache/logging/log4j/util/Strings.java
URL: 
http://svn.apache.org/viewvc/logging/log4j/log4j2/trunk/log4j-api/src/main/java/org/apache/logging/log4j/util/Strings.java?rev=1597502&r1=1597501&r2=1597502&view=diff
==============================================================================
--- 
logging/log4j/log4j2/trunk/log4j-api/src/main/java/org/apache/logging/log4j/util/Strings.java
 (original)
+++ 
logging/log4j/log4j2/trunk/log4j-api/src/main/java/org/apache/logging/log4j/util/Strings.java
 Mon May 26 02:34:51 2014
@@ -3,13 +3,16 @@ package org.apache.logging.log4j.util;
 /**
  * <em>Consider this class private.</em>
  */
-public class Strings {
+public final class Strings {
 
     /**
      * The empty string.
      */
     public static final String EMPTY = "";
 
+    private Strings() {
+    }
+
     /**
      * <p>Checks if a CharSequence is empty ("") or null.</p>
      *
@@ -38,20 +41,47 @@ public class Strings {
      * <p>Checks if a CharSequence is not empty ("") and not null.</p>
      *
      * <pre>
-     * StringUtils.isNotEmpty(null)      = false
-     * StringUtils.isNotEmpty("")        = false
-     * StringUtils.isNotEmpty(" ")       = true
-     * StringUtils.isNotEmpty("bob")     = true
-     * StringUtils.isNotEmpty("  bob  ") = true
+     * Strings.isNotEmpty(null)      = false
+     * Strings.isNotEmpty("")        = false
+     * Strings.isNotEmpty(" ")       = true
+     * Strings.isNotEmpty("bob")     = true
+     * Strings.isNotEmpty("  bob  ") = true
      * </pre>
      *
      * <p>Copied from Apache Commons Lang 
org.apache.commons.lang3.StringUtils.isNotEmpty(CharSequence)</p>
      *
      * @param cs  the CharSequence to check, may be null
      * @return {@code true} if the CharSequence is not empty and not null
-     * @since 3.0 Changed signature from isNotEmpty(String) to 
isNotEmpty(CharSequence)
      */
     public static boolean isNotEmpty(final CharSequence cs) {
         return !isEmpty(cs);
     }
+
+    /**
+     * <p>Removes control characters (char &lt;= 32) from both
+     * ends of this String returning {@code null} if the String is
+     * empty ("") after the trim or if it is {@code null}.
+     *
+     * <p>The String is trimmed using {@link String#trim()}.
+     * Trim removes start and end characters &lt;= 32.</p>
+     *
+     * <pre>
+     * Strings.trimToNull(null)          = null
+     * Strings.trimToNull("")            = null
+     * Strings.trimToNull("     ")       = null
+     * Strings.trimToNull("abc")         = "abc"
+     * Strings.trimToNull("    abc    ") = "abc"
+     * </pre>
+     *
+     * <p>Copied from Apache Commons Lang 
org.apache.commons.lang3.StringUtils.trimToNull(String)</p>
+     *
+     * @param str  the String to be trimmed, may be null
+     * @return the trimmed String,
+     *  {@code null} if only chars &lt;= 32, empty or null String input
+     */
+    public static String trimToNull(final String str) {
+        final String ts = str == null ? null : str.trim();
+        return isEmpty(ts) ? null : ts;
+    }
+
 }