added java11 cli option

Author: HugoMario

src/main/java/io/swagger/codegen/v3/generators/java/AbstractJavaCodegen.java

@@ -181,6 +181,14 @@ public AbstractJavaCodegen() {
         java8ModeOptions.put("false", "Various third party libraries as needed");
         java8Mode.setEnum(java8ModeOptions);
         cliOptions.add(java8Mode);
+
+        CliOption java11Mode = new CliOption(JAVA11_MODE, "Option. Use Java11 classes instead of third party equivalents");
+        Map<String, String> java11ModeOptions = new HashMap<String, String>();
+        java11ModeOptions.put("true", "Use Java 11 classes");
+        java11ModeOptions.put("false", "Various third party libraries as needed");
+        java11Mode.setEnum(java11ModeOptions);
+        cliOptions.add(java11Mode);
+
         cliOptions.add(CliOption.newBoolean(CHECK_DUPLICATED_MODEL_NAME, "Check if there are duplicated model names (ignoring case)"));
     }
 

src/test/java/io/swagger/codegen/v3/generators/options/JavaOptionsProvider.java

@@ -31,6 +31,7 @@ public class JavaOptionsProvider implements OptionsProvider {
     public static final String FULL_JAVA_UTIL_VALUE = "true";
     public static final String WITH_XML_VALUE = "false";
     public static final String JAVA8_MODE_VALUE = "true";
+    public static final String JAVA11_MODE_VALUE = "false";
     public static final String ENSURE_UNIQUE_PARAMS_VALUE = "true";
     //public static final String SUPPORT_JAVA6 = "true";
     public static final String USE_BEANVALIDATION = "false";
@@ -69,6 +70,7 @@ public JavaOptionsProvider() {
                 .put(JavaClientCodegen.FULL_JAVA_UTIL, FULL_JAVA_UTIL_VALUE)
                 .put(JavaClientCodegen.WITH_XML, WITH_XML_VALUE)
                 .put(JavaClientCodegen.JAVA8_MODE, JAVA8_MODE_VALUE)
+                .put(JavaClientCodegen.JAVA11_MODE, JAVA11_MODE_VALUE)
                 .put(CodegenConstants.SERIALIZE_BIG_DECIMAL_AS_STRING, "true")
                 .put(JavaClientCodegen.DATE_LIBRARY, "joda")
                 .put("hideGenerationTimestamp", "true")