我有一个场景,我在一个类中检查多个属性进行null检查。如果它不为null,我调用一个方法,它将创建一个新对象,我需要捕获这个实例对一个引用。我是成功地能够使用地图进行空检查,但无法编写代码,这将有助于我在调用后捕获返回对象。有人可以帮忙吗?
private WorkflowPreference buildWfPrefDetails(CcarReportPreferenceConfig ccarReportPreferenceConfig) {
WorkflowPreference workflowPreference = new WorkflowPreference();
List<PayloadEntry> payLoadEntries = new ArrayList<PayloadEntry>();
Optional.of(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getRwpRole)
.map(RwpRole::getRoleName)
.ifPresent(s -> workflowPreference.setKey(s));
Optional.of(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getSequenceNumber)
.ifPresent(s -> buildPayLoadEntry("SEQ_NUM", s));
Optional.of(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getSlaType)
.ifPresent(s -> buildPayLoadEntry("SLA_TYPE", s));
Optional.of(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getSlaValue)
.ifPresent(s -> buildPayLoadEntry("SLA_VALUE", s.toString()));
Optional.of(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getRejectSequence)
.ifPresent(s -> buildPayLoadEntry("REJECT_SEQUENCE", s));
Optional.of(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getRaiseQueryNotification)
.ifPresent(s -> buildPayLoadEntry("RAISE_QUERY_NOTIFICATION", s));
workflowPreference.getValue().addAll(payLoadEntries);
return workflowPreference;
}
private PayloadEntry buildPayLoadEntry(String key, String value) {
PayloadEntry payloadEntry = new PayloadEntry();
payloadEntry.setKey(key);
payloadEntry.setValue(value);
return payloadEntry;
}
预计现在:
payloadEntries列表应该在每次buildPayloadEntry调用之后捕获返回的对象。我想要实现类似下面的内容以及lambda null检查
payLoadEntries.add(buildPayLoadEntry("SEQ_NUM", ccarReportPreferenceConfig.getSequenceNumber()));
payLoadEntries.add(buildPayLoadEntry("SLA_TYPE", ccarReportPreferenceConfig.getSlaValue().toString()));
根据以下建议更新答案
Optional.ofNullable(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getRwpRole)
.map(RwpRole::getRoleName)
.ifPresent(s -> workflowPreference.setKey(s));
Optional.ofNullable(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getSequenceNumber)
.ifPresent(s -> payLoadEntries.add(buildPayLoadEntry("SEQ_NUM", s)));
Optional.ofNullable(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getSlaType)
.ifPresent(s -> payLoadEntries.add(buildPayLoadEntry("SLA_TYPE", s)));
Optional.ofNullable(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getSlaValue)
.ifPresent(s -> payLoadEntries.add(buildPayLoadEntry("SLA_VALUE", s.toString())));
Optional.ofNullable(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getRejectSequence)
.ifPresent(s -> payLoadEntries.add(buildPayLoadEntry("REJECT_SEQUENCE", s)));
Optional.ofNullable(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getRaiseQueryNotification)
.ifPresent(s -> payLoadEntries.add(buildPayLoadEntry("RAISE_QUERY_NOTIFICATION", s)));
workflowPreference.getValue().addAll(payLoadEntries);
答案 0 :(得分:1)
如果我理解正确,你只需转换(例如):
Optional.of(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getSequenceNumber)
.ifPresent(s -> buildPayLoadEntry("SEQ_NUM", s));
到
Optional.of(ccarReportPreferenceConfig)
.map(CcarReportPreferenceConfig::getSequenceNumber)
.ifPresent(s -> payLoadEntries.add(buildPayLoadEntry("SEQ_NUM", s)));