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;