org.springframework.boot.origin.Origin Maven / Gradle / Ivy
/*
* Copyright 2012-2022 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.origin;
import java.io.File;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
/**
* Interface that uniquely represents the origin of an item. For example, an item loaded
* from a {@link File} may have an origin made up of the file name along with line/column
* numbers.
*
* Implementations must provide sensible {@code hashCode()}, {@code equals(...)} and
* {@code #toString()} implementations.
*
* @author Madhura Bhave
* @author Phillip Webb
* @since 2.0.0
* @see OriginProvider
* @see TextResourceOrigin
*/
public interface Origin {
/**
* Return the parent origin for this instance if there is one. The parent origin
* provides the origin of the item that created this one.
* @return the parent origin or {@code null}
* @since 2.4.0
* @see Origin#parentsFrom(Object)
*/
default Origin getParent() {
return null;
}
/**
* Find the {@link Origin} that an object originated from. Checks if the source object
* is an {@link Origin} or {@link OriginProvider} and also searches exception stacks.
* @param source the source object or {@code null}
* @return an optional {@link Origin}
*/
static Origin from(Object source) {
if (source instanceof Origin origin) {
return origin;
}
Origin origin = null;
if (source instanceof OriginProvider originProvider) {
origin = originProvider.getOrigin();
}
if (origin == null && source instanceof Throwable throwable) {
return from(throwable.getCause());
}
return origin;
}
/**
* Find the parents of the {@link Origin} that an object originated from. Checks if
* the source object is an {@link Origin} or {@link OriginProvider} and also searches
* exception stacks. Provides a list of all parents up to root {@link Origin},
* starting with the most immediate parent.
* @param source the source object or {@code null}
* @return a list of parents or an empty list if the source is {@code null}, has no
* origin, or no parent
* @since 2.4.0
*/
static List parentsFrom(Object source) {
Origin origin = from(source);
if (origin == null) {
return Collections.emptyList();
}
Set parents = new LinkedHashSet<>();
origin = origin.getParent();
while (origin != null && !parents.contains(origin)) {
parents.add(origin);
origin = origin.getParent();
}
return Collections.unmodifiableList(new ArrayList<>(parents));
}
}