Merge pull request #21 from SimY4/master

Fixes the case where response decoders were unable to parse the type.

Author: saintf

src/main/java/feign/error/ExceptionGenerator.java

@@ -15,12 +15,14 @@
 
 import feign.Request;
 import feign.Response;
+import feign.Types;
 import feign.codec.DecodeException;
 import feign.codec.Decoder;
 import java.io.IOException;
 import java.lang.annotation.Annotation;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Type;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashMap;
@@ -46,11 +48,11 @@ class ExceptionGenerator {
   private final Integer bodyIndex;
   private final Integer headerMapIndex;
   private final Integer numOfParams;
-  private final Class bodyType;
+  private final Type bodyType;
   private final Class<? extends Exception> exceptionType;
   private final Decoder bodyDecoder;
 
-  ExceptionGenerator(Integer bodyIndex, Integer headerMapIndex, Integer numOfParams, Class bodyType,
+  ExceptionGenerator(Integer bodyIndex, Integer headerMapIndex, Integer numOfParams, Type bodyType,
       Class<? extends Exception> exceptionType, Decoder bodyDecoder) {
     this.bodyIndex = bodyIndex;
     this.headerMapIndex = headerMapIndex;
@@ -67,7 +69,7 @@ Exception createException(Response response) throws InvocationTargetException,
     Class<?>[] paramClasses = new Class[numOfParams];
     Object[] paramValues = new Object[numOfParams];
     if (bodyIndex >= 0) {
-      paramClasses[bodyIndex] = bodyType;
+      paramClasses[bodyIndex] = Types.getRawType(bodyType);
       paramValues[bodyIndex] = resolveBody(response);
     }
     if (headerMapIndex >= 0) {
@@ -84,7 +86,7 @@ Class<? extends Exception> getExceptionType() {
   }
 
   private Object resolveBody(Response response) {
-    if (bodyType.getClass().equals(Response.class)) {
+    if (bodyType instanceof Class<?> && ((Class<?>) bodyType).isInstance(response)) {
       return response;
     }
     try {
@@ -114,13 +116,13 @@ public Builder withResponseBodyDecoder(Decoder bodyDecoder) {
 
     public ExceptionGenerator build() {
       Constructor<? extends Exception> constructor = getConstructor(exceptionType);
-      Class<?>[] parameterTypes = constructor.getParameterTypes();
+      Type[] parameterTypes = constructor.getGenericParameterTypes();
       Annotation[][] parametersAnnotations = constructor.getParameterAnnotations();
 
       Integer bodyIndex = -1;
       Integer headerMapIndex = -1;
       Integer numOfParams = parameterTypes.length;
-      Class bodyType = null;
+      Type bodyType = null;
 
       for (int i = 0; i < parameterTypes.length; i++) {
         Annotation[] paramAnnotations = parametersAnnotations[i];
@@ -129,7 +131,7 @@ public ExceptionGenerator build() {
           if (annotation.annotationType().equals(ResponseHeaders.class)) {
             checkState(headerMapIndex == -1,
                 "Cannot have two parameters tagged with @ResponseHeaders");
-            checkState(parameterTypes[i].equals(Map.class),
+            checkState(Types.getRawType(parameterTypes[i]).equals(Map.class),
                 "Response Header map must be of type Map, but was %s", parameterTypes[i]);
             headerMapIndex = i;
             foundAnnotation = true;

src/test/java/feign/error/AnnotationErrorDecoderExceptionConstructorsTest.java

@@ -13,6 +13,8 @@
  */
 package feign.error;
 
+import feign.codec.Decoder;
+import feign.optionals.OptionalDecoder;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
@@ -22,6 +24,7 @@
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Optional;
 import static org.assertj.core.api.Assertions.assertThat;
 import static feign.error.AnnotationErrorDecoderExceptionConstructorsTest.TestClientInterfaceWithDifferentExceptionConstructors;
 import static feign.error.AnnotationErrorDecoderExceptionConstructorsTest.TestClientInterfaceWithDifferentExceptionConstructors.*;
@@ -69,6 +72,9 @@ public static Iterable<Object[]> data() {
             NON_NULL_HEADERS},
         {"test Declared Constructor", 509,
             DefinedConstructorWithAnnotationForNonSupportedBody.class, NULL_BODY, NO_HEADERS},
+        {"test Declared Constructor", 510,
+            DefinedConstructorWithAnnotationForOptionalBody.class, Optional.of(NON_NULL_BODY),
+            NO_HEADERS},
     });
   }
 
@@ -91,7 +97,9 @@ public static Iterable<Object[]> data() {
   public void test() throws Exception {
 
     AnnotationErrorDecoder decoder = AnnotationErrorDecoder
-        .builderFor(TestClientInterfaceWithDifferentExceptionConstructors.class).build();
+        .builderFor(TestClientInterfaceWithDifferentExceptionConstructors.class)
+        .withResponseBodyDecoder(new OptionalDecoder(new Decoder.Default()))
+        .build();
 
     Exception genericException = decoder.decode(feignConfigKey("method1Test"),
         testResponse(errorCode, NON_NULL_BODY, NON_NULL_HEADERS));
@@ -122,8 +130,9 @@ interface TestClientInterfaceWithDifferentExceptionConstructors {
         @ErrorCodes(codes = {508},
             generate = DefinedConstructorWithAnnotationForHeadersButNotForBody.class),
         @ErrorCodes(codes = {509},
-            generate = DefinedConstructorWithAnnotationForNonSupportedBody.class)
-
+            generate = DefinedConstructorWithAnnotationForNonSupportedBody.class),
+        @ErrorCodes(codes = {510},
+            generate = DefinedConstructorWithAnnotationForOptionalBody.class)
     })
     void method1Test();
 
@@ -201,6 +210,24 @@ public Object body() {
       }
     }
 
+    class DefinedConstructorWithAnnotationForOptionalBody extends ParametersException {
+      Optional<String> body;
+
+      public DefinedConstructorWithAnnotationForOptionalBody() {
+        throw new UnsupportedOperationException("Should not be called");
+      }
+
+      @FeignExceptionConstructor
+      public DefinedConstructorWithAnnotationForOptionalBody(@ResponseBody Optional<String> body) {
+        this.body = body;
+      }
+
+      @Override
+      public Object body() {
+        return body;
+      }
+    }
+
     class DefinedConstructorWithAnnotationForNonSupportedBody extends ParametersException {
       TestPojo body;