18 使用模板引擎

1       使用模板引擎

模板存放的只是文本。模板能包括引用变量和groovy代码。groovy的模板引擎提供了createTemplate 方法来实现Strings, Files, Readers or URL，返回的是Template 对象。

Template 对象通常用来创建最终的文本。Template 调用make方法，返回的是Writable，而make方法中传入的是键值对的map，而该map是传入模板的变量名及对应的值。

package template

 

import groovy.text.SimpleTemplateEngine

 

class TemplateTest {

 

    static main(args) {

       String templateText = '''Project report:

          

          

           We have currently ${tasks.size} number of items with a total duration of $duration.

           <% tasks.each{%>

              - $it.summary;

           <%}%>

       ''';

      

       def list = [

           new Task(summary:"Learn Groovy",duration:4),

           new Task(summary:"Learn Grails",duration:12)

           ];

       def totalDuration = 0;

       list.each {totalDuration+=it.duration};

       def engine = new SimpleTemplateEngine();

       def template = engine.createTemplate(templateText);

       def binding = [

           duration:"$totalDuration",

           tasks:list

           ];

       println (template.make(binding)).toString();

    }

 

}

输出

Project report:

          

          

           We have currently 2 number of items with a total duration of 16.

          

              - Learn Groovy;

          

              - Learn Grails;