| java.lang.Object
 com.sun.portal.providers.context.PropertiesFilter
All known Subclasses: com.sun.portal.providers.pctest.DateLaterThanPropertiesFilter, com.sun.portal.providers.context.ClientPropertiesFilter, com.sun.portal.providers.context.LocalePropertiesFilter,
| PropertiesFilter | | abstract public class PropertiesFilter (Code) | | This class is an abstract PropertiesFilter class. Every PropertiesFilter
implementation must extend this class.
A PropertiesFilter is used to describe an arbitrary filter
which is used to selectively look up properties with
certain criteria as well as when storing properties that are specific
to certain setting.
The PropertiesFilter itself does not compare any actual property values.
Rather, it determines if the qualifiers ('condition' and
'value') associated with the property match the filter
criteria supplied in the PropertiesFilter.
PropertiesFilters are instantiated using methods provided in
PropertiesFilterFactory and are not to be constructed directly.
In addition, PropertiesFilter objects are meant to be immutable and
stateless. Once a PropertiesFilter is initialized, the value cannot
be modified.
Nevertheless, in some cases, having an access to stateful objects
such as ProviderContext within the PropertiesFilter, especially in
the match() method may become necessary. This can be achieved by
extending the PropertierFilter in such a way that the stateful object(s)
can be passed in the constructor and stored as a member variable.
Instantiating such a PropertiesFilter is done by directly constructing
the PropertiesFilter, bypassing the PropertiesFilterFactory.
Here is an example:
public class LoggingPropertiesFilter extends PropertiesFilter {
private ProviderContext pc = null;
public LoggingPropertiesFilter(ProviderContext pc, String value, boolean required) {
super();
this.pc = pc;
try {
init(value, required);
} catch (PropertiesFilterException pfe) {
pc.debugError("LoggingPropertiesFilter(): Failed to init." , pfe);
}
}
public String getCondition() {
return "loggingEnabled";
}
public boolean match(String condition, String value) throws PropertiesFilterException {
if (!condition.equals("loggingEnabled")) {
return false;
}
if (getValue().equals(value)) {
pc.debugMessage("LoggingPropertiesFilter(): matched loggingEnabled property. value=" value);
}
return true;
}
}
List pflist = new ArrayList();
pflist.add(new LoggingPropertiesFilter(getProviderContext(), "foo", true);
Note that bypassing PropertiesFilterFactory may have a
performance impact. Also, PropertiesContext has a life-span
of one session and should not be s
Properties are looked up using different types of get/set*Property()
methods which are available in ProviderContext.
See Also: com.sun.portal.providers.context.ProviderContext
See Also: com.sun.portal.providers.context.PropertiesFilterFactory |
| Method Summary | |
| abstract public String | getCondition()
Get the condition of the filter, such as "locale" and
"client".
Filter condition is an unmodifiable constant value. | | public String | getValue()
Get the value of the filter that is associated with the condition
of the filter. | | protected void | init(String value, boolean required)
Initialize PropertiesFilter with given values.
PropertiesFilters are immutable. | | public boolean | isRequired()
Is filter required?
A conditional property lookup involves one or more property filters.
If a filter in the filter list is required, then it must match for
the overall conditional lookup to succeed. | | abstract public boolean | match(String condition, String value)
| | public String | toString()
Return a string representation of the PropertiesFilter.
Useful for debugging.
a String representation of the PropertiesFilter. |
| getCondition | | abstract public String getCondition() throws PropertiesFilterException(Code) | | Get the condition of the filter, such as "locale" and
"client".
Filter condition is an unmodifiable constant value.
filter condition
exception:
PropertiesFilterException - if there is an error in gettingthe condition of the filter. |
| getValue | | public String getValue()(Code) | | Get the value of the filter that is associated with the condition
of the filter.
filter value that was used to instantiate this PropertiesFilter. |
| init | | protected void init(String value, boolean required) throws PropertiesFilterException(Code) | | Initialize PropertiesFilter with given values.
PropertiesFilters are immutable. You cannot re-initialize an already
initialized PropertiesFilter with new values. Doing so will results
in no-op.
Parameters:
value - The value that gets associated with the filter.
Parameters:
required - Flag indicating whether this filter criteriais required or optional.
exception:
PropertiesFilterException - there was an error while initializing values |
| isRequired | | public boolean isRequired()(Code) | | Is filter required?
A conditional property lookup involves one or more property filters.
If a filter in the filter list is required, then it must match for
the overall conditional lookup to succeed. If a filter is not required,
then it can fail to match without causing the overall lookup to fail.
A chain of non-required filters can be used to implement a progressively
less-specific filter lookup, similar to the semantics of Java resource
bundle lookup.
For instance, an optional filter would be useful in a case where a
locale lookup is followed by a date lookup.
Given the filter {locale=en, locale=US, date=03/03/2003},
you can get it to successfully match a property with the qualifier
{locale=en; date=03/03/2003} even though it does not exactly match
the filter specification. This done by setting the locale filter
to be optional.
boolean indicating whether this filter is required or optional. |
| match | | abstract public boolean match(String condition, String value) throws PropertiesFilterException(Code) | | Does the given condition and value match the filter?
Parameters:
pc - ProviderContext object
Parameters:
condition - the condition to be matched against the filter condition
Parameters:
value - the value to be matched against the filter value
exception:
PropertiesFilterException - if there is an error inprocessing properties to be matched. |
| toString | | public String toString()(Code) | | Return a string representation of the PropertiesFilter.
Useful for debugging.
a String representation of the PropertiesFilter. |
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