Cleanup and test exposed utility behavior.

Author: JakeWharton

retrofit/src/main/java/retrofit2/Utils.java

@@ -36,41 +36,41 @@ private Utils() {
     // No instances.
   }
 
-  public static Class<?> getRawType(Type type) {
+  static Class<?> getRawType(Type type) {
+    if (type == null) throw new NullPointerException("type == null");
+
     if (type instanceof Class<?>) {
       // Type is a normal class.
       return (Class<?>) type;
-
-    } else if (type instanceof ParameterizedType) {
+    }
+    if (type instanceof ParameterizedType) {
       ParameterizedType parameterizedType = (ParameterizedType) type;
 
       // I'm not exactly sure why getRawType() returns Type instead of Class. Neal isn't either but
       // suspects some pathological case related to nested classes exists.
       Type rawType = parameterizedType.getRawType();
       if (!(rawType instanceof Class)) throw new IllegalArgumentException();
       return (Class<?>) rawType;
-
-    } else if (type instanceof GenericArrayType) {
+    }
+    if (type instanceof GenericArrayType) {
       Type componentType = ((GenericArrayType) type).getGenericComponentType();
       return Array.newInstance(getRawType(componentType), 0).getClass();
-
-    } else if (type instanceof TypeVariable) {
+    }
+    if (type instanceof TypeVariable) {
       // We could use the variable's bounds, but that won't work if there are multiple. Having a raw
       // type that's more general than necessary is okay.
       return Object.class;
-
-    } else if (type instanceof WildcardType) {
+    }
+    if (type instanceof WildcardType) {
       return getRawType(((WildcardType) type).getUpperBounds()[0]);
-
-    } else {
-      String className = type == null ? "null" : type.getClass().getName();
-      throw new IllegalArgumentException("Expected a Class, ParameterizedType, or "
-          + "GenericArrayType, but <" + type + "> is of type " + className);
     }
+
+    throw new IllegalArgumentException("Expected a Class, ParameterizedType, or "
+          + "GenericArrayType, but <" + type + "> is of type " + type.getClass().getName());
   }
 
   /** Returns true if {@code a} and {@code b} are equal. */
-  public static boolean equals(Type a, Type b) {
+  static boolean equals(Type a, Type b) {
     if (a == b) {
       return true; // Also handles (a == null && b == null).
 
@@ -162,7 +162,7 @@ static int hashCodeOrZero(Object o) {
     return o != null ? o.hashCode() : 0;
   }
 
-  public static String typeToString(Type type) {
+  static String typeToString(Type type) {
     return type instanceof Class ? ((Class<?>) type).getName() : type.toString();
   }
 
@@ -173,13 +173,13 @@ public static String typeToString(Type type) {
    *
    * @param supertype a superclass of, or interface implemented by, this.
    */
-  public static Type getSupertype(Type context, Class<?> contextRawType, Class<?> supertype) {
+  static Type getSupertype(Type context, Class<?> contextRawType, Class<?> supertype) {
     if (!supertype.isAssignableFrom(contextRawType)) throw new IllegalArgumentException();
     return resolve(context, contextRawType,
         getGenericSupertype(context, contextRawType, supertype));
   }
 
-  public static Type resolve(Type context, Class<?> contextRawType, Type toResolve) {
+  static Type resolve(Type context, Class<?> contextRawType, Type toResolve) {
     // This implementation is made a little more complicated in an attempt to avoid object-creation.
     while (true) {
       if (toResolve instanceof TypeVariable) {
@@ -318,9 +318,9 @@ static <T> void validateServiceInterface(Class<T> service) {
 
   static Type getParameterUpperBound(int index, ParameterizedType type) {
     Type[] types = type.getActualTypeArguments();
-    if (types.length <= index) {
+    if (index < 0 || index >= types.length) {
       throw new IllegalArgumentException(
-          "Expected at least " + index + " type argument(s) but got: " + Arrays.toString(types));
+          "Index " + index + " not in range [0," + types.length + ") for " + type);
     }
     Type paramType = types[index];
     if (paramType instanceof WildcardType) {

retrofit/src/test/java/retrofit2/CallAdapterTest.java

@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2016 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package retrofit2;
+
+import com.google.common.reflect.TypeToken;
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+import java.util.List;
+import java.util.Map;
+import org.junit.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.Assert.fail;
+import static retrofit2.CallAdapter.Factory.getParameterUpperBound;
+import static retrofit2.CallAdapter.Factory.getRawType;
+
+public final class CallAdapterTest {
+  @Test public void parameterizedTypeInvalidIndex() {
+    ParameterizedType listOfString = (ParameterizedType) new TypeToken<List<String>>() {}.getType();
+    try {
+      getParameterUpperBound(-1, listOfString);
+      fail();
+    } catch (IllegalArgumentException e) {
+      assertThat(e).hasMessage("Index -1 not in range [0,1) for java.util.List<java.lang.String>");
+    }
+    try {
+      getParameterUpperBound(1, listOfString);
+      fail();
+    } catch (IllegalArgumentException e) {
+      assertThat(e).hasMessage("Index 1 not in range [0,1) for java.util.List<java.lang.String>");
+    }
+  }
+
+  @Test public void parameterizedTypes() {
+    ParameterizedType one = (ParameterizedType) new TypeToken<List<String>>() {}.getType();
+    assertThat(getParameterUpperBound(0, one)).isSameAs(String.class);
+
+    ParameterizedType two = (ParameterizedType) new TypeToken<Map<String, String>>() {}.getType();
+    assertThat(getParameterUpperBound(0, two)).isSameAs(String.class);
+    assertThat(getParameterUpperBound(1, two)).isSameAs(String.class);
+
+    ParameterizedType wild = (ParameterizedType) new TypeToken<List<? extends CharSequence>>() {
+    }.getType();
+    assertThat(getParameterUpperBound(0, wild)).isSameAs(CharSequence.class);
+  }
+
+  @Test public void rawTypeThrowsOnNull() {
+    try {
+      getRawType(null);
+      fail();
+    } catch (NullPointerException e) {
+      assertThat(e).hasMessage("type == null");
+    }
+  }
+
+  @Test public void rawTypes() throws NoSuchMethodException {
+    assertThat(getRawType(String.class)).isSameAs(String.class);
+
+    Type listOfString = new TypeToken<List<String>>() {}.getType();
+    assertThat(getRawType(listOfString)).isSameAs(List.class);
+
+    Type stringArray = new TypeToken<String[]>() {}.getType();
+    assertThat(getRawType(stringArray)).isSameAs(String[].class);
+
+    Type wild = ((ParameterizedType) new TypeToken<List<? extends CharSequence>>() {
+    }.getType()).getActualTypeArguments()[0];
+    assertThat(getRawType(wild)).isSameAs(CharSequence.class);
+
+    Type wildParam = ((ParameterizedType) new TypeToken<List<? extends List<String>>>() {
+    }.getType()).getActualTypeArguments()[0];
+    assertThat(getRawType(wildParam)).isSameAs(List.class);
+
+    Type typeVar = A.class.getDeclaredMethod("method").getGenericReturnType();
+    assertThat(getRawType(typeVar)).isSameAs(Object.class);
+  }
+
+  @SuppressWarnings("unused") // Used reflectively.
+  static class A<T> {
+    T method() {
+      return null;
+    }
+  }
+}