我正在使用 jsf 开发网络应用程序。我尝试在 ArrayList“materialsSummaryBean.electrolyserMaterialLotList”中显示索引为 0 的元素的属性“brandName”,并为使用“c:forEach”的所有元素显示此属性。
<br/>
#{materialsSummaryBean.electrolyserMaterialLotList.get(0).material.material.brandName}
<br/>
#{materialsSummaryBean.electrolyserMaterialLotList.get(0).material.material.brandName}
<br/>
#{materialsSummaryBean.electrolyserMaterialLotList.get(0).material.material.brandName}
<br/>
#{materialsSummaryBean.electrolyserMaterialLotList.get(0).material.material.brandName}
<br/>
#{materialsSummaryBean.electrolyserMaterialLotList.get(0).material.material.brandName}
<br/>
#{materialsSummaryBean.electrolyserMaterialLotList.get(0).material.material.brandName}
<br/>
#{materialsSummaryBean.electrolyserMaterialLotList.get(0).material.material.brandName}
<br/>
#{materialsSummaryBean.electrolyserMaterialLotList.get(0).material.material.brandName}
<br/>
<hr/>
<c:forEach
items="#{materialsSummaryBean.electrolyserMaterialLotList}"
var="item" varStatus="loop">
#{item.material.material.brandName}
<br/>
#{item.material.material.brandName}
<br/>
#{item.material.material.brandName}
<br/>
#{item.material.material.brandName}
<br/>
#{item.material.material.brandName}
<br/>
#{item.material.material.brandName}
<br/>
#{item.material.material.brandName}
<br/>
<hr/>
</c:forEach>
结果,我绝对随机化了索引为 0 的元素的值列表:
ШБ-5
ЗШБ класс 4
МШ-39
ЗШБ класс 4
МШ-39
КПД-400И
ШБ-5
МШ-39
对于列表中的所有元素:
ЗШБ класс 4
ЗШБ класс 4
КПД-400И
ЗШБ класс 4
ШБ-5
МШ-39
ЗШБ класс 4
<hr />
ЗШБ класс 4
ЗШБ класс 4
МШ-39
КПД-400И
ЗШБ класс 4
ШБ-5
МШ-39
<hr />
МШ-39
КПД-400И
ЗШБ класс 4
КПД-400И
ЗШБ класс 4
ШБ-5
МШ-39
<hr />
ШБ-5
ЗШБ класс 4
МШ-39
МШ-39
ШБ-5
КПД-400И
МШ-39
<hr />
而且我不知道它是什么,有什么问题。
MaterialsSummaryBean 方法“getElectrolyserMaterialLotList”:
public List<MaterialLotSummaryData> getElectrolyserMaterialLotList() {
MaterialLotFilter materialLotFilter = new MaterialLotFilter();
materialLotFilter.setElectrolyserId(id);
return materialService.getMaterialLotByElectrolyserId(materialLotFilter);
}
和“getMaterialLotByElectrolyserId”方法:
public List<MaterialLotSummaryData> getMaterialLotByElectrolyserId(MaterialLotFilter materialLotFilter) {
Long electrolyserId = materialLotFilter.getElectrolyserId();
if (electrolyserId == null) {
throw new IllegalArgumentException("Electrolyser id cannot be null.");
}
TypedQuery<Unit> queryUnit = em.createQuery(
"select u from Unit u where u.electrolyser.id = :selectedElectrolyser",
Unit.class)
.setParameter("selectedElectrolyser", electrolyserId);
List<Unit> unitList = queryUnit.getResultList();
HashSet<MaterialLot> materialLotList = new HashSet<MaterialLot>();
HashMap<Long, Double> materialLotUsageMap = new HashMap<Long, Double>();
for (Unit unit : unitList) {
MaterialLot currentMaterialLot = unit.getMaterialLot();
if (currentMaterialLot == null) continue;
materialLotList.add(currentMaterialLot);
Double usage = unit.getActualMaterial().getAmount();
if (!materialLotUsageMap.containsKey(currentMaterialLot.getId())) {
materialLotUsageMap.put(currentMaterialLot.getId(), (usage == null) ? 0 : usage);
} else {
if(usage == null) continue;
Double currentUsage = materialLotUsageMap.get(currentMaterialLot.getId());
materialLotUsageMap.put(currentMaterialLot.getId(), currentUsage + usage);
}
}
List<MaterialLotData> result = mapper.createList(materialLotList, MaterialLotData.class);
MaterialLotSummaryData summaryData;
ArrayList<MaterialLotSummaryData> summaries = new ArrayList<MaterialLotSummaryData>();
for (MaterialLotData materialLot : result) {
if (materialLotUsageMap.containsKey(materialLot.getId())) {
summaryData = new MaterialLotSummaryData();
summaryData.setId(materialLot.getId());
summaryData.setAcceptanceDate(materialLot.getAcceptanceDate());
summaryData.setLotNumber(materialLot.getLotNumber());
summaryData.setMaterial(materialLot.getActualMaterial());
summaryData.setNumber(materialLot.getNumber());
summaryData.setManufacturer(materialLot.getManufacturer());
Double usage = materialLotUsageMap.get(materialLot.getId());
summaryData.setUsage(usage);
summaries.add(summaryData);
materialLotUsageMap.remove(materialLot.getId());
}
}
return summaries;
}