better variable and model property naming for java

modules/swagger-codegen/src/main/java/com/wordnik/swagger/codegen/DefaultCodegen.java

@@ -510,14 +510,9 @@ public class DefaultCodegen {
     if (name == null || name.length() == 0) {
       return name;
     }
-    name = toVarName(name);
-    if (name.length() > 1 && Character.isUpperCase(name.charAt(1)) &&
-            Character.isLowerCase(name.charAt(0))){
-      return name;
-    }
-    char chars[] = name.toCharArray();
-    chars[0] = Character.toUpperCase(chars[0]);
-    return new String(chars);
+
+    return camelize(toVarName(name));
+
   }
 
   public CodegenProperty fromProperty(String name, Property p) {

modules/swagger-codegen/src/main/java/com/wordnik/swagger/codegen/languages/JavaClientCodegen.java

@@ -89,13 +89,48 @@ public class JavaClientCodegen extends DefaultCodegen implements CodegenConfig {
 
   @Override
   public String toVarName(String name) {
-    if(reservedWords.contains(name))
-      return escapeReservedWord(name);
-    else {
-      return name.replaceAll("-", "_");
-    }
+    // replace - with _ e.g. created-at => created_at
+    name = name.replaceAll("-", "_");
+
+    // if it's all uppper case, do nothing
+    if (name.matches("^[A-Z_]*$"))
+      return name;
+
+    // camelize (lower first character) the variable name
+    // pet_id => petId
+    name = camelize(name, true);
+
+    // for reserved word or word starting with number, append _
+    if(reservedWords.contains(name) || name.matches("^\\d.*"))
+      name = escapeReservedWord(name);
+
+    return name;
   }
 
+  @Override
+  public String toParamName(String name) {
+    // should be the same as variable name
+    return toVarName(name);
+  }
+
+  @Override
+  public String toModelName(String name) {
+    // model name cannot use reserved keyword, e.g. return
+    if(reservedWords.contains(name))
+      throw new RuntimeException(name + " (reserved word) cannot be used as a model name");
+
+    // camelize the model name
+    // phone_number => PhoneNumber
+    return camelize(name);
+  }
+
+  @Override
+  public String toModelFilename(String name) {
+    // should be the same as the model name
+    return toModelName(name);
+  }
+
+
   @Override
   public String getTypeDeclaration(Property p) {
     if(p instanceof ArrayProperty) {
@@ -125,4 +160,4 @@ public class JavaClientCodegen extends DefaultCodegen implements CodegenConfig {
       type = swaggerType;
     return toModelName(type);
   }
-}
+}