APEX:对object中数据进行简单处理？

在Salesforce中，常常要对各种数据进行处理，已满足业务逻辑。本篇文章会介绍如何实现从object获取数据，然后将取得的数据进行一系列简单处理。

第一步：SongName__c 是一个新建的object，向SongName__c  object中插入数据：

/*向表SongName__c插入101条数据*/
    public List<SongName__c> CreateData(){
        List<SongName__c> songName = new List<SongName__c>();
        for(Integer i=0; i<101; i++){
           SongName__c a = new SongName__c(Song__c = '歌曲' + i,Contact_email__c ='wicky@sina.com',password__c ='19920122', usage__c = i+100, Active__c = true);
           songName.add(a);
       }

        try{
        insert songName;
    }
        catch(DmlException e){
            System.debug('An unexpected error has occurred'+e.getMessage());
    }
        SongName = [Select usage__c FROM SongName__c Where CreatedDate>=2016-10-22T00:00:00+08:00
                   and CreatedDate<=2016-10-27T00:00:00+08:00 ];

        system.debug('插入SongName__c的数据========================'+SongName);
        return SongName;

}    

打印出SongName__c object中的usage__c字段：

14:02:31.2 (505595323)|USER_DEBUG|[59]|DEBUG|......SongName__c.........========================(SongName__c:{usage__c=100, Id=a002800000rlMrEAAU}, SongName__c:{usage__c=101, Id=a002800000rlMrFAAU}, SongName__c:{usage__c=102, Id=a002800000rlMrGAAU}, SongName__c:{usage__c=103, Id=a002800000rlMrHAAU}, SongName__c:{usage__c=104, Id=a002800000rlMrIAAU}, SongName__c:{usage__c=105, Id=a002800000rlMrJAAU}, SongName__c:{usage__c=106, Id=a002800000rlMrKAAU}, SongName__c:{usage__c=107, Id=a002800000rlMrLAAU}, SongName__c:{usage__c=108, Id=a002800000rlMrMAAU}, SongName__c:{usage__c=109, Id=a002800000rlMrNAAU}, ...)

第二步：从 SongName__c 表中获得usage__c 字段（Decimal）的值，并调用快速排序方法将usage__c 字段的值从小到大排序。

/*从Object SongName__c 获得数据,并将获取结果排序*/
    public List<Decimal> getData(){
        List<SongName__c>  SongName=CreateData();

        Map<Id, Decimal> SongNameMap = new Map<Id, Decimal>();
        for (SongName__c sn: SongName ){
            SongNameMap.put(sn.id, sn.usage__c);
        }

        Set <Id> SongNameKey = new Set<Id>();
        List<Decimal> songnameValue = new List<Decimal>();
        SongNameKey = SongNameMap.keyset();
        for(String key: SongNameKey){
            songnameValue.add(SongNameMap.get(key));
        }
        system.debug('GET的数据是======================='+songnameValue);
        Quicksort.sortStatic(songnameValue);
        system.debug('排序结果======================='+songnameValue);
        return songnameValue;
    }

快速排序方法：

public class Quicksort  {
        private List<Decimal> mNumbers;
        private Integer mNumber;
        public static void sortStatic(List<Decimal> values){
          (new Quicksort()).sort(values);
            }//main function
            public void sort(List<Decimal> values) {

              if (values ==null || values.size()==0){
                return;
              }
              this.mNumbers = values;
              mNumber = values.size();
              quicksort(0, mNumber - 1);
            }

            private void quicksort(Integer low, Integer high) {
              Integer i = low, j = high;

              Decimal pivot = mNumbers[low + (high-low)/2];

              while (i <= j) {
                while (mNumbers[i] < pivot) {
                  i++;
                }

                while (mNumbers[j] > pivot) {
                  j--;
                }

                if (i <= j) {
                  exchange(i, j);
                  i++;
                  j--;
                }
              }
              if (low < j)
                quicksort(low, j);
              if (i < high)
                quicksort(i, high);
            }

            private void exchange(Integer i, Integer j) {
              Decimal temp = mNumbers[i];
              mNumbers[i] = mNumbers[j];
              mNumbers[j] = temp;
            }
    }

第三步：取usage__c 中最大的3个值和最小的三个值取平均然后乘以常量，常量会以随机方法生成。将结果插入表CustomerUsage__c 的UsageIndex__c字段。　

public  void insertUsage(){
        List<Decimal> songnameValue = getData();
        sortNum=songnameValue.size();
        system.debug('数组长度=================='+sortNum);
        averge= (songnameValue[0]+songnameValue[1]+songnameValue[2]+songnameValue[sortNum-3]+songnameValue[sortNum-2]+songnameValue[sortNum-1])/6;
        system.debug('平均值========================'+averge);
        sum = randomNumber * averge;
        system.debug('平均值乘以常量结果========================'+sum);
        CustomerUsage__c customnerUsage = new CustomerUsage__c();
        customnerUsage.UsageIndex__c=sum;
        insert customnerUsage;
    }

第四步：在结果插入CustomerUsage__c object 前，会触发一个Triggger，如果随机生成的常量值>0.5就发一封邮件出来，不大于0.5会抛出一个exception出来

 trigger Nov_CustomerUsage_Before_Insert on CustomerUsage__c(before insert){
        List<Messaging.SingleEmailMessage> mails = new List<Messaging.SingleEmailMessage>();
               for (CustomerUsage__c  CU : Trigger.new) {
                   if (TestUsage.randomNumber != null&& TestUsage.randomNumber > 0.5) {
                          Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
                          List<String> sendTo = new List<String>();
                          sendTo.add('weiqi.wang@novartis.com');
                          mail.setToAddresses(sendTo);
                          mail.setReplyTo('weiqi.wang@novartis.com');
                          mail.setSenderDisplayName('Official Bank of Nigeria');
                          List<String> ccTo = new List<String>();
                          ccTo.add('weiqi.a.wang@accenture.com');
                          mail.setCcAddresses(ccTo);
                          mail.setSubject('您定义的常量大于0.5');
                          String body = 'Dear '  + ', ';
                          body += '您定义的常量大于0.5';
                          mail.setHtmlBody(body);
                          mails.add(mail);
                          Messaging.sendEmail(mails);
                  }
                  if(TestUsage.randomNumber != null && TestUsage.randomNumber <=0.5){
                   CU.UsageIndex__c.addError('您定义的常量不符合规定');     

                 }

             }
 }

完整代码：

 public class TestUsage {
     public static final Decimal randomNumber = Decimal.valueOf(Math.random());//生成一个随机常量
     public Integer sortNum;//List长度
     public Decimal averge;//平均值
     public Decimal sum;

 /*插入数据到Object customnerUsage*/
     public  void TestUsage(){
         List<Decimal> songnameValue = getData();
         sortNum=songnameValue.size();
         system.debug('数组长度=================='+sortNum);
         averge= (songnameValue[0]+songnameValue[1]+songnameValue[2]+songnameValue[sortNum-3]+songnameValue[sortNum-2]+songnameValue[sortNum-1])/6;
         system.debug('平均值========================'+averge);
         sum = randomNumber * averge;
         system.debug('平均值乘以常量结果========================'+sum);
         CustomerUsage__c customnerUsage = new CustomerUsage__c();
         customnerUsage.UsageIndex__c=sum;
         insert customnerUsage;
     }
     /*从Object SongName__c 获得数据,并将获取结果排序*/
     public List<Decimal> getData(){
         List<SongName__c>  SongName=CreateData();

         Map<Id, Decimal> SongNameMap = new Map<Id, Decimal>();
         for (SongName__c sn: SongName ){
             SongNameMap.put(sn.id, sn.usage__c);
         }

         Set <Id> SongNameKey = new Set<Id>();
         List<Decimal> songnameValue = new List<Decimal>();
         SongNameKey = SongNameMap.keyset();
         for(String key: SongNameKey){
             songnameValue.add(SongNameMap.get(key));
         }
         system.debug('GET的数据是======================='+songnameValue);
         Quicksort.sortStatic(songnameValue);
         system.debug('排序结果======================='+songnameValue);
         return songnameValue;
     }
     /*向表SongName__c插入101条数据*/
     public List<SongName__c> CreateData(){
         List<SongName__c> songName = new List<SongName__c>();
         for(Integer i=0; i<101; i++){
            SongName__c a = new SongName__c(Song__c = '歌曲' + i,Contact_email__c ='wicky@sina.com',password__c ='19920122', usage__c = i+100, Active__c = true);
            songName.add(a);
        }

         try{
         insert songName;
     }
         catch(DmlException e){
             System.debug('An unexpected error has occurred'+e.getMessage());
     }
         SongName = [Select usage__c FROM SongName__c Where CreatedDate>=2016-10-22T00:00:00+08:00
                    and CreatedDate<=2016-10-27T00:00:00+08:00 ];

         system.debug('插入SongName__c的数据========================'+SongName);
         return SongName;

 }    

 }