Package org.apache.juneau.svl

Class DefaultingVar

java.lang.Object

org.apache.juneau.svl.Var

org.apache.juneau.svl.SimpleVar

org.apache.juneau.svl.DefaultingVar

Direct Known Subclasses:

ArgsVar, ConfigVar, EnvVariablesVar, FileVar, ManifestFileVar, MapVar, ServletInitParamVar

public abstract class DefaultingVar
extends SimpleVar

Interface for the resolution of vars with a default value if the resolve() method returns null.

For example, to resolve the system property "myProperty" but resolve to "not found" if the property doesn't exist: "$S{myProperty,not found}"

Subclasses must implement the following method:

• Var.resolve(VarResolverSession, String)

See Also:

• Simple Variable Language

Constructor Summary

Constructors

Constructor	Description
DefaultingVar(String name)	Constructor.

Method Summary

Modifier and Type	Method	Description
String	doResolve(VarResolverSession session, String s)	The method called from VarResolver.

Methods inherited from class org.apache.juneau.svl.SimpleVar

resolveTo

Methods inherited from class org.apache.juneau.svl.Var

allowNested, allowRecurse, canResolve, getName, resolve

Methods inherited from class java.lang.Object

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

Constructor Details

DefaultingVar

public DefaultingVar(String name)

Constructor.

Parameters:

name - The name of this variable.

Method Details

doResolve

public String doResolve(VarResolverSession session,
 String s)
                 throws Exception

Description copied from class: Var

The method called from VarResolver.

Can be overridden to intercept the request and do special handling.
Default implementation simply calls resolve(String).

Overrides:

doResolve in class Var

Parameters:

session - The session object used for a single instance of a string resolution.

s - The inside argument of the variable.

Returns:

The resolved value.

Throws:

Exception - Any exception can be thrown.