[Java][jersey3] Add error entity deserialization to ApiException

- Add errorEntity field and getErrorEntity() method to ApiException
- Add deserializeErrorEntity method to ApiClient
- Pass errorTypes map from API methods to invokeAPI
- Enables automatic deserialization of error response bodies
- Fixes #4777

Author: Chhida

modules/openapi-generator/src/main/resources/Java/libraries/jersey3/ApiClient.mustache

@@ -54,6 +54,7 @@ import java.util.List;
 import java.util.Arrays;
 import java.util.ArrayList;
 import java.util.Date;
+import java.util.Locale;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 {{#jsr310}}
@@ -1196,6 +1197,7 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
    * @param authNames The authentications to apply
    * @param returnType The return type into which to deserialize the response
    * @param isBodyNullable True if the body is nullable
+   * @param errorTypes Mapping of error codes to types into which to deserialize the response
    * @return The response body in type of string
    * @throws ApiException API exception
    */
@@ -1212,7 +1214,9 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
       String contentType,
       String[] authNames,
       GenericType<T> returnType,
-      boolean isBodyNullable)
+      boolean isBodyNullable,
+      Map<String, GenericType> errorTypes
+      )
       throws ApiException {
 
     String targetURL;
@@ -1223,7 +1227,7 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
       if (index < 0 || index >= serverConfigurations.size()) {
         throw new ArrayIndexOutOfBoundsException(
             String.format(
-                java.util.Locale.ROOT,
+                Locale.ROOT,
                 "Invalid index %d when selecting the host settings. Must be less than %d",
                 index, serverConfigurations.size()));
       }
@@ -1333,14 +1337,16 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
         String respBody = null;
         if (response.hasEntity()) {
           try {
+            // call bufferEntity, so that a subsequent call to `readEntity` in `deserialize` doesn't fail
+            response.bufferEntity();
             respBody = String.valueOf(response.readEntity(String.class));
             message = respBody;
           } catch (RuntimeException e) {
             // e.printStackTrace();
           }
         }
         throw new ApiException(
-            response.getStatus(), message, buildResponseHeaders(response), respBody);
+            response.getStatus(), message, buildResponseHeaders(response), respBody, deserializeErrorEntity(errorTypes, response));
       }
     } finally {
       try {
@@ -1351,6 +1357,21 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
       }
     }
   }
+  
+  private Object deserializeErrorEntity(Map<String, GenericType> errorTypes, Response response) {
+    if (errorTypes == null) {
+      return null;
+    }
+    GenericType errorType = errorTypes.get(String.valueOf(response.getStatus()));
+    if (errorType == null) {
+        errorType = errorTypes.get("0"); // "0" is the "default" response
+    }
+    try {
+      return deserialize(response, errorType);
+    } catch (Exception e) {
+      return String.format("Failed deserializing error entity: %s", e.toString());
+    }
+  }
 
   protected Response sendRequest(String method, Invocation.Builder invocationBuilder, Entity<?> entity) {
     Response response;
@@ -1377,7 +1398,7 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
    */
   @Deprecated
   public <T> ApiResponse<T> invokeAPI(String path, String method, List<Pair> queryParams, Object body, Map<String, String> headerParams, Map<String, String> cookieParams, Map<String, Object> formParams, String accept, String contentType, String[] authNames, GenericType<T> returnType, boolean isBodyNullable) throws ApiException {
-    return invokeAPI(null, path, method, queryParams, body, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType, isBodyNullable);
+    return invokeAPI(null, path, method, queryParams, body, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType, isBodyNullable, null/*TODO SME manage*/);
   }
 
   /**

modules/openapi-generator/src/main/resources/Java/libraries/jersey3/api.mustache

@@ -195,12 +195,20 @@ public class {{classname}} {
     {{#hasAuthMethods}}
     String[] localVarAuthNames = {{=% %=}}new String[] {%#authMethods%"%name%"%^-last%, %/-last%%/authMethods%};%={{ }}=%
     {{/hasAuthMethods}}
+    final Map<String, GenericType> localVarErrorTypes = new HashMap<String, GenericType>();
+    {{#responses}}
+    {{^-first}}
+    {{#dataType}}
+    localVarErrorTypes.put("{{code}}", new GenericType<{{{dataType}}}>() {});
+    {{/dataType}}
+    {{/-first}}
+    {{/responses}}
     {{#returnType}}
     GenericType<{{{returnType}}}> localVarReturnType = new GenericType<{{{returnType}}}>() {};
     {{/returnType}}
     return apiClient.invokeAPI("{{classname}}.{{operationId}}", {{#hasPathParams}}localVarPath{{/hasPathParams}}{{^hasPathParams}}"{{{path}}}"{{/hasPathParams}}, "{{httpMethod}}", {{#queryParams}}{{#-first}}localVarQueryParams{{/-first}}{{/queryParams}}{{^queryParams}}new ArrayList<>(){{/queryParams}}, {{#bodyParam}}{{paramName}}{{/bodyParam}}{{^bodyParam}}null{{/bodyParam}},
                                {{#headerParams}}{{#-first}}localVarHeaderParams{{/-first}}{{/headerParams}}{{^headerParams}}new LinkedHashMap<>(){{/headerParams}}, {{#cookieParams}}{{#-first}}localVarCookieParams{{/-first}}{{/cookieParams}}{{^cookieParams}}new LinkedHashMap<>(){{/cookieParams}}, {{#formParams}}{{#-first}}localVarFormParams{{/-first}}{{/formParams}}{{^formParams}}new LinkedHashMap<>(){{/formParams}}, localVarAccept, localVarContentType,
-                               {{#hasAuthMethods}}localVarAuthNames{{/hasAuthMethods}}{{^hasAuthMethods}}null{{/hasAuthMethods}}, {{#returnType}}localVarReturnType{{/returnType}}{{^returnType}}null{{/returnType}}, {{#bodyParam}}{{#isNullable}}true{{/isNullable}}{{^isNullable}}false{{/isNullable}}{{/bodyParam}}{{^bodyParam}}false{{/bodyParam}});
+                               {{#hasAuthMethods}}localVarAuthNames{{/hasAuthMethods}}{{^hasAuthMethods}}null{{/hasAuthMethods}}, {{#returnType}}localVarReturnType{{/returnType}}{{^returnType}}null{{/returnType}}, {{#bodyParam}}{{#isNullable}}true{{/isNullable}}{{^isNullable}}false{{/isNullable}}{{/bodyParam}}{{^bodyParam}}false{{/bodyParam}}, localVarErrorTypes);
   }
   {{#vendorExtensions.x-group-parameters}}
 

modules/openapi-generator/src/main/resources/Java/libraries/jersey3/apiException.mustache

@@ -20,6 +20,7 @@ public class ApiException extends{{#useRuntimeException}} RuntimeException {{/us
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
+    private Object errorEntity = null;
 
     public ApiException() {}
 
@@ -73,6 +74,11 @@ public class ApiException extends{{#useRuntimeException}} RuntimeException {{/us
         this.responseBody = responseBody;
     }
 
+    public ApiException(int code, String message, Map<String, List<String>> responseHeaders, String responseBody, Object errorEntity) {
+        this(code, message, responseHeaders, responseBody);
+        this.errorEntity = errorEntity;
+    }
+
     /**
      * Get the HTTP status code.
      *
@@ -99,4 +105,13 @@ public class ApiException extends{{#useRuntimeException}} RuntimeException {{/us
     public String getResponseBody() {
         return responseBody;
     }
+
+    /**
+     * Get the deserialized error entity (or null if this error doesn't have a model associated).
+     *
+     * @return Deserialized error entity
+     */
+    public Object getErrorEntity() {
+        return errorEntity;
+    }
 }