The fourth application example of velocity---Traversing Map collection

//2 Create a Context object
VelocityContext context = newVelocityContext();
//3 Add you data objects to this context
Map<String,String> map = newHashMap<String,String>();
map.put("key1","value1");
map.put("key2","value2");
map.put("key3","value3");
map.put("key4","value4");
context.put("map", map);
//4 Choose a template
Template template =Velocity.getTemplate("map.vm");
//5 Merge the template and you data toproduce the output
StringWriter sw = new StringWriter();
template.merge(context, sw);
sw.flush();
System.out.println(sw.toString());

#foreach($keyin $map.keySet())
$key:$map.get($key)
#end
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