org.archive.crawler.settings
Class Constraint

java.lang.Object
  org.archive.crawler.settings.Constraint

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<Constraint>

Direct Known Subclasses:

LegalValueListConstraint, LegalValueTypeConstraint, RegularExpressionConstraint

public abstract class Constraint
extends java.lang.Object
implements java.lang.Comparable<Constraint>, java.io.Serializable

Superclass for constraints that can be set on attribute definitions.

Constraints will be checked against attribute values. If a constraint check fails, an object of type FailedCheck is returned containing information that can be used to build meaningful information to the user.

A constraint has one of three levels:

• Level.SEVEREThe attribute could not be set whatsoever.
• Level.WARNINGThe attribute is illegal i CrawlJobs, but could be set in profiles. Mostly used as holder value for settings that should be changed for every entity running a crawl.
• Level.INFOThe attribute has a legal value, but is outside the bounds of what are considered a reasonable value. The user could be warned that she should investigate if the value actally is what she wants it be.

Author:

John Erik Halse

See Also:

Serialized Form

Nested Class Summary

class

Constraint.FailedCheck Objects of this class represents failed constraint checks.

Field Summary

(package private) static long

serialVersionUID

Constructor Summary

Constraint(java.util.logging.Level level, java.lang.String msg)
Constructs a new Constraint.

Method Summary

Constraint.FailedCheck	check(CrawlerSettings settings, ComplexType owner, Type definition, java.lang.Object value) Run the check.
int	compareTo(Constraint o) Compare this constraints level to another constraint.
protected java.lang.String	getDefaultMessage() Get the default message to return if a check fails.
abstract Constraint.FailedCheck	innerCheck(CrawlerSettings settings, ComplexType owner, Type definition, java.lang.Object value) The method all subclasses should implement to do the actual checking.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

serialVersionUID

static final long serialVersionUID

See Also:

Constant Field Values

Constructor Detail

Constraint

public Constraint(java.util.logging.Level level,
                  java.lang.String msg)

Constructs a new Constraint.

Parameters:

level - the level for this constraint.

msg - default message to return if the check fails.

Method Detail

check

public final Constraint.FailedCheck check(CrawlerSettings settings,
                                          ComplexType owner,
                                          Type definition,
                                          java.lang.Object value)

Run the check.

Parameters:

owner - the ComplexType owning the attribute to check.

definition - the definition to check the attribute against.

value - the value to check.

Returns:

null if ok, or an instance of Constraint.FailedCheckif the check failed.

innerCheck

public abstract Constraint.FailedCheck innerCheck(CrawlerSettings settings,
                                                  ComplexType owner,
                                                  Type definition,
                                                  java.lang.Object value)

The method all subclasses should implement to do the actual checking.

Parameters:

owner - the ComplexType owning the attribute to check.

definition - the definition to check the attribute against.

value - the value to check.

Returns:

null if ok, or an instance of Constraint.FailedCheckif the check failed.

getDefaultMessage

protected java.lang.String getDefaultMessage()

Get the default message to return if a check fails.

Returns:

the default message to return if a check fails.

compareTo

public int compareTo(Constraint o)

Compare this constraints level to another constraint. This method is implemented to let constraints be sorted with the highest level first.

Specified by:

compareTo in interface java.lang.Comparable<Constraint>

Parameters:

o - a Constraint to compare to.