"==" enum value generates "_" in Java which is invalid since Java 9 (#18338)

* #17276 "==" enum value generates "_" in Java which is invalid since Java 9

* update doc

---------

Co-authored-by: Julien BÉTI <jbeti@cosium.com>

docs/generators/groovy.md

@@ -135,6 +135,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-camel.md

@@ -174,6 +174,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-helidon-client.md

@@ -128,6 +128,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-helidon-server.md

@@ -130,6 +130,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-inflector.md

@@ -132,6 +132,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-micronaut-client.md

@@ -153,6 +153,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-micronaut-server.md

@@ -153,6 +153,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-msf4j.md

@@ -138,6 +138,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-pkmst.md

@@ -139,6 +139,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-play-framework.md

@@ -142,6 +142,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-undertow-server.md

@@ -132,6 +132,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-vertx-web.md

@@ -132,6 +132,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-vertx.md

@@ -135,6 +135,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java-wiremock.md

@@ -132,6 +132,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/java.md

@@ -164,6 +164,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/jaxrs-cxf-cdi.md

@@ -146,6 +146,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/jaxrs-cxf-client.md

@@ -137,6 +137,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/jaxrs-cxf-extended.md

@@ -160,6 +160,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/jaxrs-cxf.md

@@ -155,6 +155,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/jaxrs-jersey.md

@@ -138,6 +138,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/jaxrs-resteasy-eap.md

@@ -139,6 +139,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/jaxrs-resteasy.md

@@ -138,6 +138,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/jaxrs-spec.md

@@ -146,6 +146,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

docs/generators/spring.md

@@ -167,6 +167,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 ## RESERVED WORDS
 
 <ul class="column-ul">
+<li>_</li>
 <li>abstract</li>
 <li>apiclient</li>
 <li>apiexception</li>

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractJavaCodegen.java

@@ -192,7 +192,7 @@ public abstract class AbstractJavaCodegen extends DefaultCodegen implements Code
                         "ApiClient", "ApiException", "ApiResponse", "Configuration", "StringUtil",
 
                         // language reserved words
-                        "abstract", "continue", "for", "new", "switch", "assert",
+                        "_", "abstract", "continue", "for", "new", "switch", "assert",
                         "default", "if", "package", "synchronized", "boolean", "do", "goto", "private",
                         "this", "break", "double", "implements", "protected", "throw", "byte", "else",
                         "import", "public", "throws", "case", "enum", "instanceof", "return", "transient",
@@ -1908,10 +1908,9 @@ public abstract class AbstractJavaCodegen extends DefaultCodegen implements Code
         // string
         String var = value.replaceAll("\\W+", "_").toUpperCase(Locale.ROOT);
         if (var.matches("\\d.*")) {
-            return "_" + var;
-        } else {
-            return var;
+            var = "_" + var;
         }
+        return this.toVarName(var);
     }
 
     @Override

modules/openapi-generator/src/test/java/org/openapitools/codegen/java/AbstractJavaCodegenTest.java

@@ -56,6 +56,7 @@ public class AbstractJavaCodegenTest {
     @Test
     public void toEnumVarNameShouldNotResultInSingleUnderscore() throws Exception {
         Assert.assertEquals(fakeJavaCodegen.toEnumVarName(" ", "String"), "SPACE");
+        Assert.assertEquals(fakeJavaCodegen.toEnumVarName("==", "String"), "u");
     }
 
     @Test