add performance test

Author: XenoAmess

src/main/java/org/apache/commons/lang3/StringUtils.java

@@ -8191,12 +8191,11 @@ public static String strip(final String str) {
      * @return the stripped String, {@code null} if null String input
      */
     public static String strip(String str, final String stripChars) {
-        final int strLen = length(str);
-        if (strLen == 0) {
+        int end = length(str);
+        if (end == 0) {
             return str;
         }
         int start = 0;
-        int end = strLen;
         if (stripChars == null) {
             while (start != end && Character.isWhitespace(str.charAt(start))) {
                 start++;
@@ -8214,9 +8213,6 @@ public static String strip(String str, final String stripChars) {
                 end--;
             }
         }
-        if (start == end) {
-            return EMPTY;
-        }
         return str.substring(start, end);
     }
 

src/test/java/org/apache/commons/lang3/StringUtilsStripTest.java

@@ -29,7 +29,6 @@
 
 import java.util.concurrent.TimeUnit;
 
-import static org.apache.commons.lang3.StringUtils.EMPTY;
 import static org.apache.commons.lang3.StringUtils.INDEX_NOT_FOUND;
 import static org.apache.commons.lang3.StringUtils.isEmpty;
 import static org.apache.commons.lang3.StringUtils.length;
@@ -42,6 +41,9 @@
 @BenchmarkMode(Mode.AverageTime)
 @OutputTimeUnit(TimeUnit.NANOSECONDS)
 @State(Scope.Thread)
+@Warmup(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
+@Measurement(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
+@Fork(value = 1, jvmArgs = {"-server", "-Xms512M", "-Xmx512M"})
 public class StringUtilsStripTest {
     static final String string0 = "a";
     static final String string1 = "           a";
@@ -240,12 +242,11 @@ public void testStrings1New(Blackhole blackhole) {
     //-----
 
     public static String stripNew(String str, final String stripChars) {
-        final int strLen = length(str);
-        if (strLen == 0) {
+        int end = length(str);
+        if (end == 0) {
             return str;
         }
         int start = 0;
-        int end = strLen;
         if (stripChars == null) {
             while (start != end && Character.isWhitespace(str.charAt(start))) {
                 start++;
@@ -263,9 +264,6 @@ public static String stripNew(String str, final String stripChars) {
                 end--;
             }
         }
-        if (start == end) {
-            return EMPTY;
-        }
         return str.substring(start, end);
     }