Array Filter
Recently I needed a way to quickly filter out an array (i.e. list) of sObjects in Apex. Since I was a C# developer for 5 years, I immediately remembered how I used LINQ in C# for this purpose and I hoped there’s something similar in Apex as well. However, in Apex, there is no easy way to filter through a list without using the for loop.
I’m usually trying to limit the number of DML statements in Apex, so I’d often query more records at once (if I know I’m not going to reach 50.000 records limit) and then filter through it via for loop in case I need to get multiple sets of records from that query. Because of this need, I decided to create a helper class that will help me achieve this without writing the for loop every time I need to filter something. I’m sharing the class with you below, and you can share your thoughts with me in the comments.
public class ArrayFilter {
public static List<sObject> filter(List<sObject> arrayToFilter, List<ArrayFilter.Filter> filters, String filterLogic){
List<sObject> retVal = new List<sObject>();
if(arrayToFilter == null){
return retVal;
}
if(filterLogic == 'OR'){
for(Integer i = 0; i < arrayToFilter.size(); i++){
for(Integer j = 0; j < filters.size(); j++){
Filter f = filters[j];
if(ArrayFilter.Assert(arrayToFilter[i], f)){
retVal.add(arrayToFilter[i]);
continue;
}
}
}
}else if(filterLogic == 'AND'){
for(Integer i = 0; i < arrayToFilter.size(); i++){
Boolean passedTheFilter = true;
for(Integer j = 0; j < filters.size(); j++){
Filter f = filters[j];
if(ArrayFilter.Assert(arrayToFilter[i], f) == false){
passedTheFilter = false;
break;
}
}
if(passedTheFilter){
retVal.add(arrayToFilter[i]);
}
}
}else{
throw new ArrayFilterException('Invalid filter logic "' + filterLogic + '" in class ArrayFilter. \n\nAvailable options are "OR" and "AND"');
}
return retVal;
}
public static Boolean Assert(sObject o, Filter f){
if(f.valueType == 'Boolean'){
if(f.operator == '!='){
return ((Boolean)o.get(f.fieldName)) != f.valBoolean;
}else{
return ((Boolean)o.get(f.fieldName)) == f.valBoolean;
}
}else if(f.valueType == 'Date'){
if(f.operator == '!='){
return ((Date)o.get(f.fieldName)) != f.valDate;
}else if(f.operator == '>'){
return ((Date)o.get(f.fieldName)) > f.valDate;
}else if(f.operator == '<'){
return ((Date)o.get(f.fieldName)) < f.valDate;
}else{
return ((Date)o.get(f.fieldName)) == f.valDate;
}
}else if(f.valueType == 'DateTime'){
if(f.operator == '!='){
return ((DateTime)o.get(f.fieldName)) != f.valDateTime;
}else if(f.operator == '>'){
return ((DateTime)o.get(f.fieldName)) > f.valDateTime;
}else if(f.operator == '<'){
return ((DateTime)o.get(f.fieldName)) < f.valDateTime;
}else{
return ((DateTime)o.get(f.fieldName)) == f.valDateTime;
}
}else if(f.valueType == 'Time'){
if(f.operator == '!='){
return ((Time)o.get(f.fieldName)) != f.valTime;
}else if(f.operator == '>'){
return ((Time)o.get(f.fieldName)) > f.valTime;
}else if(f.operator == '<'){
return ((Time)o.get(f.fieldName)) < f.valTime;
}else{
return ((Time)o.get(f.fieldName)) == f.valTime;
}
}else if(f.valueType == 'Integer'){
if(f.operator == '!='){
return ((Integer)o.get(f.fieldName)) != f.valInteger;
}else if(f.operator == '>'){
return ((Integer)o.get(f.fieldName)) > f.valInteger;
}else if(f.operator == '<'){
return ((Integer)o.get(f.fieldName)) < f.valInteger;
}else{
return ((Integer)o.get(f.fieldName)) == f.valInteger;
}
}else if(f.valueType == 'Decimal'){
if(f.operator == '!='){
return ((Decimal)o.get(f.fieldName)) != f.valDecimal;
}else if(f.operator == '>'){
return ((Decimal)o.get(f.fieldName)) > f.valDecimal;
}else if(f.operator == '<'){
return ((Decimal)o.get(f.fieldName)) < f.valDecimal;
}else{
return ((Decimal)o.get(f.fieldName)) == f.valDecimal;
}
}else if(f.valueType == 'Double'){
if(f.operator == '!='){
return ((Double)o.get(f.fieldName)) != f.valDouble;
}else if(f.operator == '>'){
return ((Double)o.get(f.fieldName)) > f.valDouble;
}else if(f.operator == '<'){
return ((Double)o.get(f.fieldName)) < f.valDouble;
}else{
return ((Double)o.get(f.fieldName)) == f.valDouble;
}
}else if(f.valueType == 'Long'){
if(f.operator == '!='){
return ((Long)o.get(f.fieldName)) != f.valLong;
}else if(f.operator == '>'){
return ((Long)o.get(f.fieldName)) > f.valLong;
}else if(f.operator == '<'){
return ((Long)o.get(f.fieldName)) < f.valLong;
}else{
return ((Long)o.get(f.fieldName)) == f.valLong;
}
}else if(f.valueType == 'Id'){
if(f.operator == '!='){
return ((Id)o.get(f.fieldName)) != f.valId;
}else{
return ((Id)o.get(f.fieldName)) == f.valId;
}
}else if(f.valueType == 'String'){
if(f.operator == '!='){
return !((String)o.get(f.fieldName)).equals(f.valString);
}else if(f.operator == 'CONTAINS'){
return ((String)o.get(f.fieldName)).contains(f.valString);
}else if(f.operator == 'STARTS'){
return ((String)o.get(f.fieldName)).startsWith(f.valString);
}else if(f.operator == 'ENDS'){
return ((String)o.get(f.fieldName)).endsWith(f.valString);
}else{
return ((String)o.get(f.fieldName)).equals(f.valString);
}
}
return false;
}
public class Filter {
public String fieldName {get; private set;}
public String valueType {get; private set;}
public String operator {get; private set;}//>,<,=,!=, CONTAINS, STARTS, ENDS
public Boolean valBoolean {get; private set;}
public Date valDate {get; private set;}
public DateTime valDateTime {get; private set;}
public Time valTime {get; private set;}
public Integer valInteger {get; private set;}
public Decimal valDecimal {get; private set;}
public Double valDouble {get; private set;}
public Long valLong {get; private set;}
public Id valId {get; private set;}
public String valString {get; private set;}
public Filter(String fieldName, String operator, Boolean value){
this.fieldName = fieldName;
this.valueType = 'Boolean';
this.valBoolean = value;
this.operator = operator;
}
public Filter(String fieldName, String operator, Date value){
this.fieldName = fieldName;
this.valueType = 'Date';
this.valDate = value;
this.operator = operator;
}
public Filter(String fieldName, String operator, DateTime value){
this.fieldName = fieldName;
this.valueType = 'DateTime';
this.valDateTime = value;
this.operator = operator;
}
public Filter(String fieldName, String operator, Time value){
this.fieldName = fieldName;
this.valueType = 'Time';
this.valTime = value;
this.operator = operator;
}
public Filter(String fieldName, String operator, Integer value){
this.fieldName = fieldName;
this.valueType = 'Integer';
this.valInteger = value;
this.operator = operator;
}
public Filter(String fieldName, String operator, Decimal value){
this.fieldName = fieldName;
this.valueType = 'Decimal';
this.valDecimal = value;
this.operator = operator;
}
public Filter(String fieldName, String operator, Double value){
this.fieldName = fieldName;
this.valueType = 'Double';
this.valDouble = value;
this.operator = operator;
}
public Filter(String fieldName, String operator, Long value){
this.fieldName = fieldName;
this.valueType = 'Long';
this.valLong = value;
this.operator = operator;
}
public Filter(String fieldName, String operator, Id value){
this.fieldName = fieldName;
this.valueType = 'Id';
this.valId = value;
this.operator = operator;
}
public Filter(String fieldName, String operator, String value){
this.fieldName = fieldName;
this.valueType = 'String';
this.valString = value;
this.operator = operator;
}
}
}Sample usage
Below you can see some of the ways you could use this ArrayFilter class to filter a list of objects.
Example #1:
//filter by String
List<sObject> filteredArray = ArrayFilter.filter(someArrayToFilter, new ArrayFilter.Filter[]{new ArrayFilter.Filter('Name', '=', 'John Doe')}, 'OR');Example #2:
List<ArrayFilter.Filter> filters = new List<ArrayFilter.Filter>();
filters.add(new ArrayFilter.Filter('Migration_Start_Date__c', '=', Date.newInstance(2000,1,2)));
filters.add(new ArrayFilter.Filter('Migration_Start_Date__c', '>', Date.newInstance(2010,3,4)));
List<Account> filtered = ArrayFilter.filter(someArrayToFilter,filters, 'OR');Example #3:
//text supports operators: =, !=, CONTAINS, ENDS, STARTS
List<ArrayFilter.Filter> filters = new List<ArrayFilter.Filter>();
filters.add(new ArrayFilter.Filter('Phone', 'STARTS', '0355'));
filters.add(new ArrayFilter.Filter('NAME', 'STARTS', 'Jo'));
List<Account> filtered = ArrayFilter.filter(someArrayToFilter,filters, 'AND');
Written on May 15, 2016