chore(perf): Avoid using trim when checking whether is blank or not.

nstdio · Sep 15, 2023 · 3dc9372 · 3dc9372
1 parent b5c307f
commit 3dc9372
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Showing 2 changed files with 18 additions and 2 deletions.
diff --git a/src/main/java/cz/jirutka/rsql/parser/ast/StringUtils.java b/src/main/java/cz/jirutka/rsql/parser/ast/StringUtils.java
@@ -38,6 +38,22 @@ public static String join(List<?> list, String delimiter, String prefix, String
     }
 
     public static boolean isBlank(String str) {
-        return str == null || str.trim().isEmpty();
+        return str == null || (indexOfNonWhitespace(str) == str.length());
+    }
+
+    /**
+     * Copied from JDK 20
+     */
+    private static int indexOfNonWhitespace(String s) {
+        int length = s.length() >> 1;
+        int left = 0;
+        while (left < length) {
+            int codepoint = s.codePointAt(left);
+            if (codepoint != ' ' && codepoint != '\t' && !Character.isWhitespace(codepoint)) {
+                break;
+            }
+            left += Character.charCount(codepoint);
+        }
+        return left;
     }
 }
diff --git a/src/test/groovy/cz/jirutka/rsql/parser/ast/ComparisonOperatorTest.groovy b/src/test/groovy/cz/jirutka/rsql/parser/ast/ComparisonOperatorTest.groovy
@@ -40,7 +40,7 @@ class ComparisonOperatorTest extends Specification {
         then:
             thrown IllegalArgumentException
         where:
-            sym << [null, '', 'foo', '=123=', '=', '=<', '=>', '=!', 'a=b=c']
+            sym << [null, '', ' ', 'foo', '=123=', '=', '=<', '=>', '=!', 'a=b=c']
     }
 
     def 'equals when contains same symbols'() {