hudson.model.Resource Maven / Gradle / Ivy
package hudson.model;
/**
* Represents things that {@link Queue.Executable} uses while running.
*
*
* This is used in {@link Queue} to support basic mutual exclusion/locks. If two
* {@link Queue.Task}s require the same {@link Resource}, they will not
* be run at the same time.
*
*
* Resources are compared by using their {@link #displayName names}, and
* need not have the "same object" semantics.
*
* @since 1.121
*/
public final class Resource {
/**
* Human-readable name of this resource.
* Used for rendering HTML.
*/
public final String displayName;
/**
* Parent resource.
*
*
* A child resource is considered a part of the parent resource,
* so acquiring the parent resource always imply acquiring all
* the child resources.
*/
public final Resource parent;
/**
* Maximum number of concurrent write.
*/
public final int numConcurrentWrite;
public Resource(Resource parent, String displayName) {
this(parent,displayName,1);
}
/**
* @since 1.155
*/
public Resource(Resource parent, String displayName, int numConcurrentWrite) {
if(numConcurrentWrite<1)
throw new IllegalArgumentException();
this.parent = parent;
this.displayName = displayName;
this.numConcurrentWrite = numConcurrentWrite;
}
public Resource(String displayName) {
this(null,displayName);
}
/**
* Checks the resource collision.
*
* @param count
* If we are testing W/W conflict, total # of write counts.
* For R/W conflict test, this value should be set to {@link Integer#MAX_VALUE}.
*/
public boolean isCollidingWith(Resource that, int count) {
assert that!=null;
for(Resource r=that; r!=null; r=r.parent)
if(this.equals(r) && r.numConcurrentWrite