org.apache.juneau.svl.DefaultingVar Maven / Gradle / Ivy
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// * *
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package org.apache.juneau.svl;
import static org.apache.juneau.internal.StringUtils.*;
/**
* 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:
*
* - {@link #resolve(VarResolverSession, String)}
*
*
* See Also:
*
* - {@doc juneau-svl.SvlVariables}
*
*/
public abstract class DefaultingVar extends SimpleVar {
/**
* Constructor.
*
* @param name The name of this variable.
*/
public DefaultingVar(String name) {
super(name);
}
@Override /* Var*/
public String doResolve(VarResolverSession session, String s) throws Exception {
int i = s.indexOf(',');
if (i == -1)
return resolve(session, s.trim());
String[] s2 = split(s);
String v = resolve(session, s2[0]);
if (v == null)
v = s2[1];
return v;
}
}