Copyright (c) 2003, 2012 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
IBM - Initial API and implementation
/*******************************************************************************
* Copyright (c) 2003, 2012 IBM Corporation and others.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* Contributors:
* IBM - Initial API and implementation
*******************************************************************************/
package org.eclipse.core.runtime.jobs;
Scheduling rules are used by jobs to indicate when they need exclusive access
to a resource. Scheduling rules can also be applied synchronously to a thread
using IJobManager.beginRule(ISchedulingRule) and
IJobManager.endRule(ISchedulingRule). The job manager guarantees that
no two jobs with conflicting scheduling rules will run concurrently.
Multiple rules can be applied to a given thread only if the outer rule explicitly
allows the nesting as specified by the contains method.
Clients may implement this interface.
See Also: Since: 3.0
/**
* Scheduling rules are used by jobs to indicate when they need exclusive access
* to a resource. Scheduling rules can also be applied synchronously to a thread
* using <code>IJobManager.beginRule(ISchedulingRule)</code> and
* <code>IJobManager.endRule(ISchedulingRule)</code>. The job manager guarantees that
* no two jobs with conflicting scheduling rules will run concurrently.
* Multiple rules can be applied to a given thread only if the outer rule explicitly
* allows the nesting as specified by the <code>contains</code> method.
* <p>
* Clients may implement this interface.
* </p>
*
* @see Job#getRule()
* @see Job#setRule(ISchedulingRule)
* @see Job#schedule(long)
* @see IJobManager#beginRule(ISchedulingRule, org.eclipse.core.runtime.IProgressMonitor)
* @see IJobManager#endRule(ISchedulingRule)
* @since 3.0
*/
public interface ISchedulingRule {
Returns whether this scheduling rule completely contains another scheduling
rule. Rules can only be nested within a thread if the inner rule is completely
contained within the outer rule.
Implementations of this method must obey the rules of a partial order relation
on the set of all scheduling rules. In particular, implementations must be reflexive
(a.contains(a) is always true), antisymmetric (a.contains(b) and b.contains(a) iff a.equals(b),
and transitive (if a.contains(b) and b.contains(c), then a.contains(c)). Implementations
of this method must return false when compared to a rule they
know nothing about.
Params: - rule – the rule to check for containment
Returns: true if this rule contains the given rule, and
false otherwise.
/**
* Returns whether this scheduling rule completely contains another scheduling
* rule. Rules can only be nested within a thread if the inner rule is completely
* contained within the outer rule.
* <p>
* Implementations of this method must obey the rules of a partial order relation
* on the set of all scheduling rules. In particular, implementations must be reflexive
* (a.contains(a) is always true), antisymmetric (a.contains(b) and b.contains(a) iff a.equals(b),
* and transitive (if a.contains(b) and b.contains(c), then a.contains(c)). Implementations
* of this method must return <code>false</code> when compared to a rule they
* know nothing about.
*
* @param rule the rule to check for containment
* @return <code>true</code> if this rule contains the given rule, and
* <code>false</code> otherwise.
*/
boolean contains(ISchedulingRule rule);
Returns whether this scheduling rule is compatible with another scheduling rule.
If true is returned, then no job with this rule will be run at the
same time as a job with the conflicting rule. If false is returned,
then the job manager is free to run jobs with these rules at the same time.
Implementations of this method must be reflexive, symmetric, and consistent,
and must return false when compared to a rule they know
nothing about.
This method must return true if calling contains(ISchedulingRule) on the same rule also returns true. This is required because it would otherwise allow two threads to be running concurrently with the same rule.
Params: - rule – the rule to check for conflicts
Returns: true if the rule is conflicting, and false
otherwise.
/**
* Returns whether this scheduling rule is compatible with another scheduling rule.
* If <code>true</code> is returned, then no job with this rule will be run at the
* same time as a job with the conflicting rule. If <code>false</code> is returned,
* then the job manager is free to run jobs with these rules at the same time.
* <p>
* Implementations of this method must be reflexive, symmetric, and consistent,
* and must return <code>false</code> when compared to a rule they know
* nothing about.
* <p>
* This method must return true if calling {@link #contains(ISchedulingRule)} on
* the same rule also returns true. This is required because it would otherwise
* allow two threads to be running concurrently with the same rule.
*
* @param rule the rule to check for conflicts
* @return <code>true</code> if the rule is conflicting, and <code>false</code>
* otherwise.
*/
boolean isConflicting(ISchedulingRule rule);
}