Fix #94 Create TypeInfo#equalTo(Class) and TypeInfo#isAssignableFrom(Class)

Author: ljacqu

src/main/java/ch/jalu/typeresolver/TypeInfo.java

@@ -155,7 +155,40 @@ public Class<?> getSafeToReadClass() {
     }
 
     /**
-     * Returns a type info of the enclosing type (i.e. the outer class if this type is an nested class).
+     * Returns whether this type info, as class ({@link #toClass()}), is equal to the given class.
+     * <p>Examples:<ul>
+     *  <li>{@code new TypeInfo(String.class).equalTo(String.class) // true}</li>
+     *  <li>{@code new TypeReference<List<String>>() { }.equalTo(List.class) // true}</li>
+     *  <li>{@code new TypeReference<List<String>>() { }.equalTo(ArrayList.class) // false}</li>
+     * </ul>
+     *
+     * @param clazz the class to check for equality
+     * @return true if this type info converts to the same class as the given one, false otherwise
+     */
+    public boolean equalTo(Class<?> clazz) {
+        return clazz.equals(toClass());
+    }
+
+    /**
+     * Returns whether the class represented by this type info is equal or assignable from the given class. In other
+     * words, this TypeInfo's {@link #toClass()} checks with {@link Class#isAssignableFrom} whether the given class
+     * is equal or an extension of this type info's class.
+     * <p>Examples:<ul>
+     *  <li>{@code new TypeInfo(String.class).isAssignableFrom(Double.class) // false}</li>
+     *  <li>{@code new TypeReference<List<String>>() { }.isAssignableFrom(List.class) // true}</li>
+     *  <li>{@code new TypeReference<List<String>>() { }.isAssignableFrom(ArrayList.class) // true}</li>
+     * </ul>
+     *
+     * @param clazz the class to check with
+     * @return true if this type info's class is equal or a supertype of the given class, false otherwise
+     */
+    public boolean isAssignableFrom(Class<?> clazz) {
+        Class<?> thisClass = toClass();
+        return thisClass != null && thisClass.isAssignableFrom(clazz);
+    }
+
+    /**
+     * Returns a type info of the enclosing type (i.e. the outer class if this type is a nested class).
      * Returns null if not applicable.
      *
      * @return the enclosing type, or null if this type is not a nested type

src/test/java/ch/jalu/typeresolver/TypeInfoTest.java

@@ -12,6 +12,7 @@
 import ch.jalu.typeresolver.samples.typeinheritance.IntegerDoubleArgProcessorExtension;
 import ch.jalu.typeresolver.samples.typeinheritance.OneArgProcessor;
 import ch.jalu.typeresolver.samples.typeinheritance.StringArgProcessorExtension;
+import ch.jalu.typeresolver.typeimpl.WildcardTypeImpl;
 import org.junit.jupiter.api.Test;
 
 import java.io.Serializable;
@@ -370,6 +371,36 @@ void shouldThrowForConstructorWithNotOverriddenMethod() {
         assertThrows(UnsupportedOperationException.class, TypeInfo::new);
     }
 
+    @Test
+    void shouldReturnWhetherIsEqualToClass() {
+        // given / when / then
+        assertThat(new TypeInfo(String.class).equalTo(String.class), equalTo(true));
+        assertThat(getType("stringList").equalTo(List.class), equalTo(true));
+        assertThat(new NestedTypeReference<List<? super Number>>() { }.equalTo(Number.class), equalTo(true));
+
+        assertThat(new TypeInfo(String.class).equalTo(double.class), equalTo(false));
+        assertThat(getType("stringList").equalTo(ArrayList.class), equalTo(false));
+        assertThat(getType("stringList").equalTo(Collection.class), equalTo(false));
+        assertThat(new TypeInfo(WildcardTypeImpl.newUnboundedWildcard()).equalTo(Object.class), equalTo(false));
+    }
+
+    @Test
+    void shouldReturnWhetherIsAssignableFromClass() {
+        // given / when / then
+        assertThat(new TypeInfo(String.class).isAssignableFrom(String.class), equalTo(true));
+        assertThat(new TypeInfo(CharSequence.class).isAssignableFrom(String.class), equalTo(true));
+
+        assertThat(getType("stringList").isAssignableFrom(List.class), equalTo(true));
+        assertThat(getType("stringList").isAssignableFrom(ArrayList.class), equalTo(true));
+        assertThat(new NestedTypeReference<List<? super Number>>() { }.isAssignableFrom(Number.class), equalTo(true));
+        assertThat(new NestedTypeReference<List<? super Number>>() { }.isAssignableFrom(Integer.class), equalTo(true));
+
+        assertThat(new TypeInfo(String.class).isAssignableFrom(double.class), equalTo(false));
+        assertThat(getType("stringList").isAssignableFrom(Collection.class), equalTo(false));
+        assertThat(new NestedTypeReference<List<? super Number>>() { }.isAssignableFrom(int.class), equalTo(false));
+        assertThat(new TypeInfo(WildcardTypeImpl.newUnboundedWildcard()).isAssignableFrom(Object.class), equalTo(false));
+    }
+
     private static TypeInfo getType(String fieldName) {
         try {
             return new TypeInfo(ParameterizedTypes.class.getDeclaredField(fieldName).getGenericType());