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Spring Cloud Contract Shaded Dependencies
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.commons.lang3.reflect;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import org.apache.commons.lang3.Validate;
/**
* Type literal comparable to {@code javax.enterprise.util.TypeLiteral},
* made generally available outside the JEE context. Allows the passing around of
* a "token" that represents a type in a typesafe manner, as opposed to
* passing the (non-parameterized) {@link Type} object itself. Consider:
*
* You might see such a typesafe API as:
*
* class Typesafe {
* <T> T obtain(Class<T> type, ...);
* }
*
* Consumed in the manner of:
*
* Foo foo = typesafe.obtain(Foo.class, ...);
*
* Yet, you run into problems when you want to do this with a parameterized type:
*
* List<String> listOfString = typesafe.obtain(List.class, ...); // could only give us a raw List
*
* {@code java.lang.reflect.Type} might provide some value:
*
* Type listOfStringType = ...; // firstly, how to obtain this? Doable, but not straightforward.
* List<String> listOfString = (List<String>) typesafe.obtain(listOfStringType, ...); // nongeneric Type would necessitate a cast
*
* The "type literal" concept was introduced to provide an alternative, i.e.:
*
* class Typesafe {
* <T> T obtain(TypeLiteral<T> type, ...);
* }
*
* Consuming code looks like:
*
* List<String> listOfString = typesafe.obtain(new TypeLiteral<List<String>>() {}, ...);
*
*
* This has the effect of "jumping up" a level to tie a {@code java.lang.reflect.Type}
* to a type variable while simultaneously making it short work to obtain a
* {@link Type} instance for any given type, inline.
*
* Additionally {@link TypeLiteral} implements the {@link Typed} interface which
* is a generalization of this concept, and which may be implemented in custom classes.
* It is suggested that APIs be defined in terms of the interface, in the following manner:
*
*
* <T> T obtain(Typed<T> typed, ...);
*
*
* @param the type
* @since 3.2
*/
public abstract class TypeLiteral implements Typed {
@SuppressWarnings("rawtypes")
private static final TypeVariable> T = TypeLiteral.class.getTypeParameters()[0];
/**
* Represented type.
*/
public final Type value;
private final String toString;
/**
* The default constructor.
*/
protected TypeLiteral() {
this.value =
Validate.notNull(TypeUtils.getTypeArguments(getClass(), TypeLiteral.class).get(T),
"%s does not assign type parameter %s", getClass(), TypeUtils.toLongString(T));
this.toString = String.format("%s<%s>", TypeLiteral.class.getSimpleName(), TypeUtils.toString(value));
}
@Override
public final boolean equals(final Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof TypeLiteral)) {
return false;
}
final TypeLiteral other = (TypeLiteral) obj;
return TypeUtils.equals(value, other.value);
}
@Override
public int hashCode() {
return 37 << 4 | value.hashCode();
}
@Override
public String toString() {
return toString;
}
@Override
public Type getType() {
return value;
}
}