org.apache.juneau.svl.StreamedVar Maven / Gradle / Ivy
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// * *
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package org.apache.juneau.svl;
/**
* Abstract superclass of all Simple Var Language variables that write their values directly to a writer.
*
*
* Note the difference between this class and {@link SimpleVar} that returns simple string values.
*
Unlike the {@link SimpleVar} class, the output from this class cannot contain nested variables.
*
However, this class can be more efficient for variables that produce large amounts of output so that the creation
* of large in-memory strings is avoided.
*
*
* Subclasses must implement the following method:
*
* - {@link #resolveTo(VarResolverSession, java.io.Writer, String)}
*
*
* See Also:
*
* - {@doc juneau-svl.SvlVariables}
*
*/
public abstract class StreamedVar extends Var {
/**
* Constructor.
*
* @param name The variable name (e.g. "C" for variables of the form "$C{...}" )
*/
public StreamedVar(String name) {
super(name, true);
}
@Override /* Var */
public String resolve(VarResolverSession session, String arg) throws Exception {
throw new UnsupportedOperationException("Cannot call resolve() on StreamedVar class");
}
}