org.springframework.boot.context.properties.bind.Bindable Maven / Gradle / Ivy
/*
* Copyright 2012-2019 the original author or authors.
*
* 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
*
* https://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.springframework.boot.context.properties.bind;
import java.lang.annotation.Annotation;
import java.lang.reflect.Array;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.function.Supplier;
import org.springframework.core.ResolvableType;
import org.springframework.core.style.ToStringCreator;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;
/**
* Source that can be bound by a {@link Binder}.
*
* @param the source type
* @author Phillip Webb
* @author Madhura Bhave
* @since 2.0.0
* @see Bindable#of(Class)
* @see Bindable#of(ResolvableType)
*/
public final class Bindable {
private static final Annotation[] NO_ANNOTATIONS = {};
private final ResolvableType type;
private final ResolvableType boxedType;
private final Supplier value;
private final Annotation[] annotations;
private Bindable(ResolvableType type, ResolvableType boxedType, Supplier value, Annotation[] annotations) {
this.type = type;
this.boxedType = boxedType;
this.value = value;
this.annotations = annotations;
}
/**
* Return the type of the item to bind.
* @return the type being bound
*/
public ResolvableType getType() {
return this.type;
}
/**
* Return the boxed type of the item to bind.
* @return the boxed type for the item being bound
*/
public ResolvableType getBoxedType() {
return this.boxedType;
}
/**
* Return a supplier that provides the object value or {@code null}.
* @return the value or {@code null}
*/
public Supplier getValue() {
return this.value;
}
/**
* Return any associated annotations that could affect binding.
* @return the associated annotations
*/
public Annotation[] getAnnotations() {
return this.annotations;
}
/**
* Return a single associated annotations that could affect binding.
* @param the annotation type
* @param type annotation type
* @return the associated annotation or {@code null}
*/
@SuppressWarnings("unchecked")
public A getAnnotation(Class type) {
for (Annotation annotation : this.annotations) {
if (type.isInstance(annotation)) {
return (A) annotation;
}
}
return null;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null || getClass() != obj.getClass()) {
return false;
}
Bindable other = (Bindable) obj;
boolean result = true;
result = result && nullSafeEquals(this.type.resolve(), other.type.resolve());
result = result && nullSafeEquals(this.annotations, other.annotations);
return result;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ObjectUtils.nullSafeHashCode(this.type);
result = prime * result + ObjectUtils.nullSafeHashCode(this.annotations);
return result;
}
@Override
public String toString() {
ToStringCreator creator = new ToStringCreator(this);
creator.append("type", this.type);
creator.append("value", (this.value != null) ? "provided" : "none");
creator.append("annotations", this.annotations);
return creator.toString();
}
private boolean nullSafeEquals(Object o1, Object o2) {
return ObjectUtils.nullSafeEquals(o1, o2);
}
/**
* Create an updated {@link Bindable} instance with the specified annotations.
* @param annotations the annotations
* @return an updated {@link Bindable}
*/
public Bindable withAnnotations(Annotation... annotations) {
return new Bindable<>(this.type, this.boxedType, this.value,
(annotations != null) ? annotations : NO_ANNOTATIONS);
}
/**
* Create an updated {@link Bindable} instance with an existing value.
* @param existingValue the existing value
* @return an updated {@link Bindable}
*/
public Bindable withExistingValue(T existingValue) {
Assert.isTrue(
existingValue == null || this.type.isArray() || this.boxedType.resolve().isInstance(existingValue),
() -> "ExistingValue must be an instance of " + this.type);
Supplier value = (existingValue != null) ? () -> existingValue : null;
return new Bindable<>(this.type, this.boxedType, value, this.annotations);
}
/**
* Create an updated {@link Bindable} instance with a value supplier.
* @param suppliedValue the supplier for the value
* @return an updated {@link Bindable}
*/
public Bindable withSuppliedValue(Supplier suppliedValue) {
return new Bindable<>(this.type, this.boxedType, suppliedValue, this.annotations);
}
/**
* Create a new {@link Bindable} of the type of the specified instance with an
* existing value equal to the instance.
* @param the source type
* @param instance the instance (must not be {@code null})
* @return a {@link Bindable} instance
* @see #of(ResolvableType)
* @see #withExistingValue(Object)
*/
@SuppressWarnings("unchecked")
public static Bindable ofInstance(T instance) {
Assert.notNull(instance, "Instance must not be null");
Class type = (Class) instance.getClass();
return of(type).withExistingValue(instance);
}
/**
* Create a new {@link Bindable} of the specified type.
* @param the source type
* @param type the type (must not be {@code null})
* @return a {@link Bindable} instance
* @see #of(ResolvableType)
*/
public static Bindable of(Class type) {
Assert.notNull(type, "Type must not be null");
return of(ResolvableType.forClass(type));
}
/**
* Create a new {@link Bindable} {@link List} of the specified element type.
* @param the element type
* @param elementType the list element type
* @return a {@link Bindable} instance
*/
public static Bindable> listOf(Class elementType) {
return of(ResolvableType.forClassWithGenerics(List.class, elementType));
}
/**
* Create a new {@link Bindable} {@link Set} of the specified element type.
* @param the element type
* @param elementType the set element type
* @return a {@link Bindable} instance
*/
public static Bindable> setOf(Class elementType) {
return of(ResolvableType.forClassWithGenerics(Set.class, elementType));
}
/**
* Create a new {@link Bindable} {@link Map} of the specified key and value type.
* @param the key type
* @param the value type
* @param keyType the map key type
* @param valueType the map value type
* @return a {@link Bindable} instance
*/
public static Bindable> mapOf(Class keyType, Class valueType) {
return of(ResolvableType.forClassWithGenerics(Map.class, keyType, valueType));
}
/**
* Create a new {@link Bindable} of the specified type.
* @param the source type
* @param type the type (must not be {@code null})
* @return a {@link Bindable} instance
* @see #of(Class)
*/
public static Bindable of(ResolvableType type) {
Assert.notNull(type, "Type must not be null");
ResolvableType boxedType = box(type);
return new Bindable<>(type, boxedType, null, NO_ANNOTATIONS);
}
private static ResolvableType box(ResolvableType type) {
Class resolved = type.resolve();
if (resolved != null && resolved.isPrimitive()) {
Object array = Array.newInstance(resolved, 1);
Class wrapperType = Array.get(array, 0).getClass();
return ResolvableType.forClass(wrapperType);
}
if (resolved != null && resolved.isArray()) {
return ResolvableType.forArrayComponent(box(type.getComponentType()));
}
return type;
}
}