[Java] Escaping properties for java (#628)

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

@@ -761,6 +761,8 @@ public class DefaultCodegen implements CodegenConfig {
     public String toVarName(String name) {
         if (reservedWords.contains(name)) {
             return escapeReservedWord(name);
+        } else if (((CharSequence) name).chars().anyMatch(character -> specialCharReplacements.keySet().contains( "" + ((char) character)))) {
+            return escapeSpecialCharacters(name, null, null);
         } else {
             return name;
         }
@@ -777,6 +779,8 @@ public class DefaultCodegen implements CodegenConfig {
         name = removeNonNameElementToCamelCase(name); // FIXME: a parameter should not be assigned. Also declare the methods parameters as 'final'.
         if (reservedWords.contains(name)) {
             return escapeReservedWord(name);
+        } else if (((CharSequence) name).chars().anyMatch(character -> specialCharReplacements.keySet().contains( "" + ((char) character)))) {
+            return escapeSpecialCharacters(name, null, null);
         }
         return name;
     }
@@ -815,6 +819,32 @@ public class DefaultCodegen implements CodegenConfig {
         throw new RuntimeException("reserved word " + name + " not allowed");
     }
 
+    /**
+     * Return the name with escaped characters.
+     *
+     * @param name the name to be escaped
+     * @param charactersToAllow characters that are not escaped
+     * @param appdendixToReplacement String to append to replaced characters.
+     * @return the escaped word
+     * <p>
+     * throws Runtime exception as word is not escaped properly.
+     */
+    public String escapeSpecialCharacters(String name, List<String> charactersToAllow, String appdendixToReplacement) {
+        String result = (String) ((CharSequence) name).chars().mapToObj(c -> {
+          String character = "" + (char) c;
+          if (charactersToAllow != null && charactersToAllow.contains(character)) {
+              return character;
+          } else if (specialCharReplacements.containsKey(character)) {
+              return specialCharReplacements.get(character) + (appdendixToReplacement != null ? appdendixToReplacement: "");
+          } else {
+              return character;
+          }
+        }).reduce( (c1, c2) -> "" + c1 + c2).orElse(null);
+
+        if (result != null) return result;
+        throw new RuntimeException("Word '" + name + "' could not be escaped.");
+    }
+
     /**
      * Return the fully-qualified "Model" name for import
      *

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

@@ -574,6 +574,14 @@ public abstract class AbstractJavaCodegen extends DefaultCodegen implements Code
             name = name.substring(0, 2).toLowerCase() + name.substring(2);
         }
 
+        // If name contains special chars -> replace them.
+        if ((((CharSequence) name).chars().anyMatch(character -> specialCharReplacements.keySet().contains( "" + ((char) character))))) {
+            List<String> allowedCharacters = new ArrayList<>();
+            allowedCharacters.add("_");
+            allowedCharacters.add("$");
+            name = escapeSpecialCharacters(name, allowedCharacters, "_");
+        }
+
         // camelize (lower first character) the variable name
         // pet_id => petId
         name = camelize(name, true);

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

@@ -242,6 +242,31 @@ public class JavaModelTest {
         Assert.assertTrue(property.isContainer);
     }
 
+    @Test(description = "convert a model with restriced characters")
+    public void restrictedCharactersPropertiesTest() {
+        final Schema schema = new Schema()
+                .description("a sample model")
+                .addProperties("@Some:restricted%characters#to!handle+", new BooleanSchema());
+        final DefaultCodegen codegen = new JavaClientCodegen();
+        final CodegenModel cm = codegen.fromModel("sample", schema, Collections.singletonMap("sample", schema));
+
+        Assert.assertEquals(cm.name, "sample");
+        Assert.assertEquals(cm.classname, "Sample");
+        Assert.assertEquals(cm.description, "a sample model");
+        Assert.assertEquals(cm.vars.size(), 1);
+
+        final CodegenProperty property = cm.vars.get(0);
+        Assert.assertEquals(property.baseName, "@Some:restricted%characters#to!handle+");
+        Assert.assertEquals(property.getter, "getAtSomeColonRestrictedPercentCharactersHashToExclamationHandlePlus");
+        Assert.assertEquals(property.setter, "setAtSomeColonRestrictedPercentCharactersHashToExclamationHandlePlus");
+        Assert.assertEquals(property.dataType, "Boolean");
+        Assert.assertEquals(property.name, "atSomeColonRestrictedPercentCharactersHashToExclamationHandlePlus");
+        Assert.assertEquals(property.defaultValue, "null");
+        Assert.assertEquals(property.baseType, "Boolean");
+        Assert.assertFalse(property.required);
+        Assert.assertTrue(property.isNotContainer);
+    }
+
     @Test(description = "convert a model with complex properties")
     public void complexPropertiesTest() {
         final Schema schema = new Schema()