StringRules

SUGGESTION

Simplification

View source code on GitHub

Suppression

Disable all rules by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$).* as compiler argument.

Table of contents

1. StringIsEmpty
2. StringIsEmptyPredicate
3. StringIsNotEmptyPredicate
4. StringIsNullOrEmpty
5. OptionalNonEmptyString
6. FilterEmptyString
7. JoinStrings
8. StringValueOf
9. NewStringFromCharArraySubSequence
10. NewStringFromCharArray
11. StringValueOfMethodReference
12. SubstringRemainder
13. Utf8EncodedLength
14. StringIndexOfChar
15. StringIndexOfString
16. StringLastIndexOfChar
17. StringLastIndexOfString
18. StringLastIndexOfCharWithIndex
19. StringLastIndexOfStringWithIndex
20. StringStartsWith

StringIsEmpty

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringIsEmpty") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringIsEmpty).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 ImmutableSet<Boolean> testStringIsEmpty() {
   return ImmutableSet.of(
-      "foo".length() == 0,
-      "bar".length() <= 0,
-      "baz".length() < 1,
-      "foo".length() != 0,
-      "bar".length() > 0,
-      "baz".length() >= 1);
+      "foo".isEmpty(),
+      "bar".isEmpty(),
+      "baz".isEmpty(),
+      !"foo".isEmpty(),
+      !"bar".isEmpty(),
+      !"baz".isEmpty());
 }

StringIsEmptyPredicate

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringIsEmptyPredicate") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringIsEmptyPredicate).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 boolean testStringIsEmptyPredicate() {
-  return Stream.of("foo").anyMatch(s -> s.isEmpty());
+  return Stream.of("foo").anyMatch(String::isEmpty);
 }

StringIsNotEmptyPredicate

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringIsNotEmptyPredicate") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringIsNotEmptyPredicate).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 boolean testStringIsNotEmptyPredicate() {
-  return Stream.of("foo").anyMatch(s -> !s.isEmpty());
+  return Stream.of("foo").anyMatch(not(String::isEmpty));
 }

StringIsNullOrEmpty

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringIsNullOrEmpty") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringIsNullOrEmpty).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 ImmutableSet<Boolean> testStringIsNullOrEmpty() {
   return ImmutableSet.of(
-      getClass().getName() == null || getClass().getName().isEmpty(),
-      getClass().getName() != null && !getClass().getName().isEmpty());
+      Strings.isNullOrEmpty(getClass().getName()), !Strings.isNullOrEmpty(getClass().getName()));
 }

OptionalNonEmptyString

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("OptionalNonEmptyString") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$OptionalNonEmptyString).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 ImmutableSet<Optional<String>> testOptionalNonEmptyString() {
   return ImmutableSet.of(
-      Strings.isNullOrEmpty(toString()) ? Optional.empty() : Optional.of(toString()),
-      Strings.isNullOrEmpty(toString()) ? Optional.empty() : Optional.ofNullable(toString()),
-      !Strings.isNullOrEmpty(toString()) ? Optional.of(toString()) : Optional.empty(),
-      !Strings.isNullOrEmpty(toString()) ? Optional.ofNullable(toString()) : Optional.empty());
+      Optional.ofNullable(toString()).filter(Predicate.not(String::isEmpty)),
+      Optional.ofNullable(toString()).filter(Predicate.not(String::isEmpty)),
+      Optional.ofNullable(toString()).filter(Predicate.not(String::isEmpty)),
+      Optional.ofNullable(toString()).filter(Predicate.not(String::isEmpty)));
 }

FilterEmptyString

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("FilterEmptyString") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$FilterEmptyString).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 Optional<String> testFilterEmptyString() {
-  return Optional.of("foo").map(Strings::emptyToNull);
+  return Optional.of("foo").filter(not(String::isEmpty));
 }

JoinStrings

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("JoinStrings") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$JoinStrings).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 ImmutableSet<String> testJoinStrings() {
   return ImmutableSet.of(
-      Joiner.on("a").join(new String[] {"foo", "bar"}),
-      Joiner.on("b").join(new CharSequence[] {"foo", "bar"}),
-      Arrays.stream(new String[] {"foo", "bar"}).collect(joining("c")),
-      Joiner.on("d").join(ImmutableList.of("foo", "bar")),
-      Streams.stream(Iterables.cycle(ImmutableList.of("foo", "bar"))).collect(joining("e")),
-      ImmutableList.of("foo", "bar").stream().collect(joining("f")));
+      String.join("a", new String[] {"foo", "bar"}),
+      String.join("b", new CharSequence[] {"foo", "bar"}),
+      String.join("c", new String[] {"foo", "bar"}),
+      String.join("d", ImmutableList.of("foo", "bar")),
+      String.join("e", Iterables.cycle(ImmutableList.of("foo", "bar"))),
+      String.join("f", ImmutableList.of("foo", "bar")));
 }

StringValueOf

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringValueOf") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringValueOf).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 String testStringValueOf() {
-  return Objects.toString("foo");
+  return String.valueOf("foo");
 }

NewStringFromCharArraySubSequence

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("NewStringFromCharArraySubSequence") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$NewStringFromCharArraySubSequence).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 ImmutableSet<String> testNewStringFromCharArraySubSequence() {
   return ImmutableSet.of(
-      String.valueOf(new char[] {'f', 'o', 'o'}, 0, 1),
-      String.copyValueOf(new char[] {'b', 'a', 'r'}, 2, 3));
+      new String(new char[] {'f', 'o', 'o'}, 0, 1), new String(new char[] {'b', 'a', 'r'}, 2, 3));
 }

NewStringFromCharArray

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("NewStringFromCharArray") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$NewStringFromCharArray).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 ImmutableSet<String> testNewStringFromCharArray() {
   return ImmutableSet.of(
-      String.valueOf(new char[] {'f', 'o', 'o'}),
-      new String(new char[] {'b', 'a', 'r'}, 0, new char[] {'b', 'a', 'r'}.length));
+      new String(new char[] {'f', 'o', 'o'}), new String(new char[] {'b', 'a', 'r'}));
 }

StringValueOfMethodReference

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringValueOfMethodReference") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringValueOfMethodReference).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 Function<Object, String> testStringValueOfMethodReference() {
-  return Objects::toString;
+  return String::valueOf;
 }

SubstringRemainder

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("SubstringRemainder") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$SubstringRemainder).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 String testSubstringRemainder() {
-  return "foo".substring(1, "foo".length());
+  return "foo".substring(1);
 }

Utf8EncodedLength

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("Utf8EncodedLength") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$Utf8EncodedLength).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 int testUtf8EncodedLength() {
-  return "foo".getBytes(UTF_8).length;
+  return Utf8.encodedLength("foo");
 }

StringIndexOfChar

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringIndexOfChar") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringIndexOfChar).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 int testStringIndexOfChar() {
-  return "foo".substring(1).indexOf('a');
+  return Math.max(-1, "foo".indexOf('a', 1) - 1);
 }

StringIndexOfString

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringIndexOfString") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringIndexOfString).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 int testStringIndexOfString() {
-  return "foo".substring(1).indexOf("bar");
+  return Math.max(-1, "foo".indexOf("bar", 1) - 1);
 }

StringLastIndexOfChar

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringLastIndexOfChar") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringLastIndexOfChar).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 int testStringLastIndexOfChar() {
-  return "foo".substring(1).lastIndexOf('a');
+  return Math.max(-1, "foo".lastIndexOf('a') - 1);
 }

StringLastIndexOfString

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringLastIndexOfString") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringLastIndexOfString).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 int testStringLastIndexOfString() {
-  return "foo".substring(1).lastIndexOf("bar");
+  return Math.max(-1, "foo".lastIndexOf("bar") - 1);
 }

StringLastIndexOfCharWithIndex

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringLastIndexOfCharWithIndex") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringLastIndexOfCharWithIndex).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 int testStringLastIndexOfCharWithIndex() {
-  return "foo".substring(0, 2).lastIndexOf('a');
+  return "foo".lastIndexOf('a', 2 - 1);
 }

StringLastIndexOfStringWithIndex

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringLastIndexOfStringWithIndex") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringLastIndexOfStringWithIndex).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 int testStringLastIndexOfStringWithIndex() {
-  return "foo".substring(0, 2).lastIndexOf("bar");
+  return "foo".lastIndexOf("bar", 2 - 1);
 }

StringStartsWith

SUGGESTION

Simplification

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("StringStartsWith") to the enclosing element.

Disable this rule by adding -XepOpt:Refaster:NamePattern=^(?!StringRules\$StringStartsWith).* as compiler argument.

Samples

Shows the difference in example code before and after the Refaster rule is applied.

 boolean testStringStartsWith() {
-  return "foo".substring(1).startsWith("bar");
+  return "foo".startsWith("bar", 1);
 }