feat: Adding basic error type support for output units.

src/main/generated/io/vertx/json/schema/OutputUnitConverter.java

@@ -65,6 +65,11 @@ static void fromJson(Iterable<java.util.Map.Entry<String, Object>> json, OutputU
             obj.setAnnotations(list);
           }
           break;
+        case "errorType":
+          if (member.getValue() instanceof String) {
+            obj.setErrorType(io.vertx.json.schema.OutputErrorType.valueOf((String)member.getValue()));
+          }
+          break;
       }
     }
   }
@@ -99,5 +104,8 @@ static void toJson(OutputUnit obj, java.util.Map<String, Object> json) {
       obj.getAnnotations().forEach(item -> array.add(item.toJson()));
       json.put("annotations", array);
     }
+    if (obj.getErrorType() != null) {
+      json.put("errorType", obj.getErrorType().name());
+    }
   }
 }

src/main/java/io/vertx/json/schema/JsonSchemaValidationException.java

@@ -18,19 +18,24 @@
 public final class JsonSchemaValidationException extends Exception {
 
   final private String location;
+  final private OutputErrorType errorType;
 
-  public JsonSchemaValidationException(String message, Throwable cause, String location) {
+  public JsonSchemaValidationException(String message, Throwable cause, String location, OutputErrorType errorType) {
     super(message, cause);
     this.location = location;
+    this.errorType = errorType;
   }
 
-  public JsonSchemaValidationException(String message, String location, StackTraceElement stackTraceElement) {
-    this(message, null, location, stackTraceElement);
+  public JsonSchemaValidationException(String message, String location, OutputErrorType errorType,
+                                       StackTraceElement stackTraceElement) {
+    this(message, null, location, errorType, stackTraceElement);
   }
 
-  public JsonSchemaValidationException(String message, Throwable cause, String location, StackTraceElement stackTraceElement) {
+  public JsonSchemaValidationException(String message, Throwable cause, String location, OutputErrorType errorType,
+                                       StackTraceElement stackTraceElement) {
     super(message, cause, stackTraceElement != null, stackTraceElement != null);
     this.location = location;
+    this.errorType = errorType;
     if (stackTraceElement != null) {
       setStackTrace(new StackTraceElement[]{
         stackTraceElement
@@ -45,4 +50,12 @@ public JsonSchemaValidationException(String message, Throwable cause, String loc
   public String location() {
     return location;
   }
+
+  /**
+   * @return our best guess on what the validation error type is.
+   */
+  public OutputErrorType errorType() {
+    return errorType;
+  }
+
 }

src/main/java/io/vertx/json/schema/OutputErrorType.java

@@ -0,0 +1,12 @@
+package io.vertx.json.schema;
+
+import io.vertx.codegen.annotations.VertxGen;
+
+@VertxGen
+public enum OutputErrorType {
+
+  NONE,
+  INVALID_VALUE,
+  MISSING_VALUE
+
+}

src/main/java/io/vertx/json/schema/OutputUnit.java

@@ -29,6 +29,7 @@ public class OutputUnit {
   private String keywordLocation;
   private String instanceLocation;
   private String error;
+  private OutputErrorType errorType = OutputErrorType.NONE;
 
   private List<OutputUnit> errors;
   private List<OutputUnit> annotations;
@@ -44,11 +45,12 @@ public OutputUnit(boolean valid) {
     this.valid = valid;
   }
 
-  public OutputUnit(String instanceLocation, String absoluteKeywordLocation, String keywordLocation, String error) {
+  public OutputUnit(String instanceLocation, String absoluteKeywordLocation, String keywordLocation, String error, OutputErrorType errorType) {
     this.instanceLocation = instanceLocation;
     this.absoluteKeywordLocation = absoluteKeywordLocation;
     this.keywordLocation = keywordLocation;
     this.error = error;
+    this.errorType = errorType;
   }
 
   public Boolean getValid() {
@@ -132,6 +134,15 @@ public OutputUnit setAnnotations(List<OutputUnit> annotations) {
     return this;
   }
 
+  public OutputErrorType getErrorType() {
+    return errorType;
+  }
+
+  public OutputUnit setErrorType(OutputErrorType errorType) {
+    this.errorType = errorType;
+    return this;
+  }
+
   public OutputUnit addAnnotation(OutputUnit annotation) {
     if (this.annotations == null) {
       this.annotations = new ArrayList<>();
@@ -161,6 +172,7 @@ public void checkValidity() throws JsonSchemaValidationException {
       throw new JsonSchemaValidationException(
         msg == null ? "JsonSchema Validation error" : msg,
         location,
+        errorType,
         // add some information to the stack trace
         createStackTraceElement());
     } else {
@@ -173,6 +185,7 @@ public void checkValidity() throws JsonSchemaValidationException {
           throw new JsonSchemaValidationException(
             msg == null ? "JsonSchema Validation error" : msg,
             location,
+            errorType,
             // add some information to the stack trace
             createStackTraceElement());
         } else {
@@ -186,6 +199,7 @@ public void checkValidity() throws JsonSchemaValidationException {
               error.getError(),
               lastException,
               location,
+              errorType,
               // add some information to the stack trace
               error.createStackTraceElement());
             lastException = cause;
@@ -194,7 +208,7 @@ public void checkValidity() throws JsonSchemaValidationException {
             throw lastException;
           } else {
             // one final wrap as there is extra error message in the unit
-            throw new JsonSchemaValidationException(msg, lastException, getAbsoluteKeywordLocation());
+            throw new JsonSchemaValidationException(msg, lastException, getAbsoluteKeywordLocation(), errorType);
           }
         }
       }