题目要求实现一个Apex类,在查询所有Opportunity时,根据Opportunity的CloseDate属性将Opportunity按时间顺序排列,并且在Opportunity与其关联的Account之间创建一个Lookup字段。
以下是代码示例:
public class OpportunityController {
public static void createLookupFieldOnAccount() {
// 创建Opportunity对Account的Lookup字段
Schema.SObjectType opportunitySchema = Schema.getGlobalDescribe().get('Opportunity');
Schema.SObjectField accountIdField = opportunitySchema.getDescribe().fields.getMap().get('AccountId');
List accountSObjectTypeList = new List{Schema.Account.getSObjectType()};
Schema.DescribeSObjectResult accountDescribeResult = accountSObjectTypeList[0].getDescribe();
String accountSObjectApiName = accountDescribeResult.getName();
String opportunitySObjectApiName = opportunitySchema.getDescribe().getName();
String lookupFieldName = 'Account__c';
if(accountDescribeResult.fields.getMap().get(lookupFieldName) == null) {
Schema.SObjectField lookupField = Schema.SObjectType.Opportunity.fields.getMap().get(lookupFieldName);
Schema.ReferenceFieldDefinition referenceField = new Schema.ReferenceFieldDefinition(opportunitySObjectApiName, lookupFieldName, opportunitySObjectApiName, accountIdField);
referenceField.setRelationshipName('Opportunities');
List fieldSetMembers = new List{new Schema.FieldSetMember('Opportunities', lookupFieldName)};
accountDescribeResult.fields.getMap().get('Id').getDescribe().getFieldSets().get('Opportunities').add(fieldSetMembers);
}
}
public static List getListOrderByCloseDate() {
createLookupFieldOnAccount();
// 查询所有Opportunity并按CloseDate升序排序
return [SELECT Id, Name, CloseDate, AccountId, Account.Name FROM Opportunity ORDER BY CloseDate ASC];
}
}
在代码中,我们首先通过Schema API自动创建Opportunity对Account的Lookup字段,然后在查询Opportunity时进行排序。最后,我们可以在Opportunity和关联的Account之间建立关联。
注意:为了在Op