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package org.apache.juneau.svl; | |
/** | |
* Interface for the resolution of vars with a default value if the <c>resolve()</c> method returns <jk>null</jk>. | |
* | |
* <p> | |
* For example, to resolve the system property <js>"myProperty"</js> but resolve to <js>"not found"</js> if the | |
* property doesn't exist: <js>"$S{myProperty,not found}"</js> | |
* | |
* <p> | |
* Subclasses must implement the following method: | |
* <ul class='javatree'> | |
* <li class='jm'>{@link #resolve(VarResolverSession, String)} | |
* </ul> | |
* | |
* <ul class='seealso'> | |
* <li class='link'>{@doc juneau-marshall.SimpleVariableLanguage.SvlVariables} | |
* </ul> | |
*/ | |
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 s1 = s.substring(0, i); | |
String s2 = s.length() == i ? null : s.substring(i+1); | |
String v = resolve(session, s1); | |
if (v == null) | |
v = s2; | |
return v; | |
} | |
} |