如何在速度模板中迭代嵌套地图？

Question

如何在速度模板中迭代嵌套地图？我有

HashMap<String, HashMap<String, HashMap<String, List<MealPlanGroup>>>> termPlans=new HashMap<String, HashMap<String, HashMap<String, List<MealPlanGroup>>>>();

这张地图我在 java 中填充了数据并呈现到 html 页面但无法在 html 页面上迭代

Answer 1

鉴于您已将那个可怕的变量绑定到模板中的 termPlans 变量，您可以执行以下操作：

#foreach( $level1 in $termPlans )
    <!-- Iterating over the values of the first Map level -->
    #foreach( $level2 in $level1 )
        <!-- Iterating over the values of the second Map level -->
        #foreach( $list in $level2 )
            <!-- Iterating over the values of the third Map level -->
            #foreach( $mealPlanGroup in $list )
                <!-- Iterating over the values of the List -->
                $mealPlanGroup.id <br/>
            #end
        #end
    #end
#end

这只会使用地图值，而会忽略它们的键。如果您还需要密钥，您可以尝试遍历 entrySet():

#foreach( $level1Entry in $termPlans.entrySet() )
    <!-- Iterating over the values of the first Map level -->
    Level 1 key is $level1Entry.getKey()

    #foreach( $level2Entry in $level1Entry.getValue().entrySet() )
        Level 2 key is $level2Entry.getKey()

        <!-- Iterating over the values of the second Map level -->
        #foreach( $level3Entry in $level2Entry.getValue().entrySet() )
            Level 3 key is $level3Entry.getKey()

            <!-- Iterating over the values of the third Map level -->
            #foreach( $mealPlanGroup in $level3Entry.getValue() )
                <!-- Iterating over the values of the List -->
                $mealPlanGroup.id <br/>
            #end
        #end
    #end
#end

如何在速度模板中迭代嵌套地图？

How to iterate nested map in velocity template?

html

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velocity

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