How to Use macro to wrap HTML tags in java

import java.io.StringWriter;
import java.io.Writer;

import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.Velocity;
import org.apache.velocity.tools.generic.IteratorTool;

public class VMDemo {

public static void main(String[] args) throws Exception {
Velocity.init();

Template t = Velocity.getTemplate("./src/demo.vm");

VelocityContext ctx = new VelocityContext();
ctx.put("var", new IteratorTool());

Writer writer = new StringWriter();
t.merge(ctx, writer);

System.out.println(writer);
}
}
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#macro( d )

#end

#d()