How To Debug Apex Code Without Losing Your Mind
Apex does not come with a pause button. There is no traditional breakpoint that stops execution and lets you poke around. What Salesforce gives you instead is a set of logging, inspection, and replay tools that, used well, make finding the problem faster than most developers expect. This guide covers the practical workflow from first error to confirmed fix, with examples at each step. Step 1: read the error before you do anything else Most debugging sessions start with someone jumping straight into the code. The error message is still the fastest path to the problem, and it is worth reading carefully before opening any tool. Salesforce Apex errors typically tell you the class name, the line number, and the exception type. A System.NullPointerException at line 42 in AccountTriggerHandler is telling you exactly where to look. A System.LimitException: Too many SOQL queries: 101 is telling you the problem is structural, not a typo. The three most common Apex exceptions and what they signal: NullPointerException A variable you expected to have a value is null. Usually means a query returned no records, or an object field was never set. LimitException A governor limit was hit. SOQL inside a loop is the classic cause of the 101 SOQL queries error. DmlException A database operation failed. Required field missing, validation rule violation, or duplicate record are the usual culprits. Step 2: add System.debug() to trace what is happening System.debug() is the starting point for most Apex debugging. It writes output to the debug log, which you can then read to understand what your code was actually doing at each point. Place debug statements before and after the line you suspect is failing, and log the values of the variables involved. Basic System.debug() usage Account acc = [SELECT Id, Name, OwnerId FROM Account WHERE Id = :accountId LIMIT 1]; System.debug('Account retrieved: ' + acc); System.debug('Owner ID: ' + acc.OwnerId); The LoggingLevel parameter controls how much noise you produce in the log. Use LoggingLevel.DEBUG for general tracing and LoggingLevel.ERROR for conditions that should never occur. Using log levels to filter output System.debug(LoggingLevel.DEBUG, 'Entering processAccount method'); System.debug(LoggingLevel.ERROR, 'Account is null – this should not happen'); System.debug(LoggingLevel.FINEST, 'Loop iteration value: ' + i); Setting the log level to FINEST captures everything. That is useful when you have no idea where the problem is. Once you narrow the location down, reduce it to DEBUG to keep the log readable. Step 3: enable debug logs and read them in Developer Console Debug statements only appear if logging is active for the user running the code. Setting up a trace flag takes two minutes and is required before any logging will appear. Go to Setup search for Debug Logs in the Quick Find box. Click New select the user you want to trace, set an expiry time, and choose a debug level. Start with SFDC_DevConsole if you are not sure which level to use. Reproduce the issue trigger the code by running the action that causes the error. Open Developer Console go to the Logs tab and double-click the most recent log entry. Use the filter type the class or method name you are debugging to isolate relevant lines from the noise. The log output includes a timestamp, event type, and the message from your System.debug() call. What to look for: USER_DEBUG lines contain your System.debug() output SOQL_EXECUTE lines show every query that ran and how many rows it returned DML_BEGIN and DML_END wrap every database operation CUMULATIVE_LIMIT_USAGE near the end of the log shows governor limit consumption Step 4: use Execute Anonymous to isolate and test When you want to test a specific piece of logic without triggering the full context of a trigger or flow, Execute Anonymous is the fastest tool available. It runs Apex directly in the org against real data, and the debug log appears immediately. Open it from Developer Console under Debug, then Open Execute Anonymous Window. Testing a query and inspecting results in isolation Id testAccountId = '0015g00000XXXXXX'; List<Account> accts = [ SELECT Id, Name, AnnualRevenue, OwnerId FROM Account WHERE Id = :testAccountId ]; System.debug('Records found: ' + accts.size()); if (!accts.isEmpty()) { System.debug('Account name: ' + accts[0].Name); System.debug('Annual revenue: ' + accts[0].AnnualRevenue); } This approach lets you confirm whether the data you expect to be there actually is, before assuming the logic is wrong. Many debugging sessions end here because the data was the problem, not the code. Step 5: use Apex Replay Debugger for complex flows For situations where System.debug() alone is not enough, VS Code’s Apex Replay Debugger lets you step through a captured debug log line by line, inspect variable values at each point, and set breakpoints on specific lines without stopping real execution. This is the closest Apex gets to a traditional debugger, and it is free with the Salesforce Extension Pack for VS Code. Open the Apex class or trigger in VS Code click in the gutter to the left of the line numbers to set a breakpoint. Enable the replay debugger open the Command Palette with Ctrl+Shift+P and run SFDX: Turn On Apex Debug Log for Replay Debugger. Reproduce the issue in the org trigger the code that is failing. Fetch the log Command Palette, then SFDX: Get Apex Debug Logs, and select the relevant log. Launch the replay Command Palette, then SFDX: Launch Apex Replay Debugger with Current File. Execution will pause at your breakpoints and you can inspect variable values in the VS Code sidebar. Replay Debugger does not run code again. It replays a captured log, so the variable values you see reflect what actually happened during the original execution. This is exactly what makes it useful for reproducing intermittent bugs. Step 6: identify governor limit issues before they become production problems Governor limits are the category of Apex errors that can reach production undetected in low-volume testing and then fail at scale. The most common is the 101 SOQL queries limit caused by queries inside loops. The pattern that causes 101
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How to develop flexible Apex code for Salesforce
Day-to-day developer work related not only with writing new functionality but updating existing ones. When a developer tasked with adding a new feature to an existing application, the goal is to extend the functionality of that application with new behaviors. Extending software is the introduction of a new behavior by the addition of code. Some applications are flexible to this kind of change, whereas others may fight you tooth and nail! Flexibility is how easily software can adapt to shifting requirements. In an ideal extensible system, adding new behavior involves strictly adding new code without changing existing code. Adding new behavior to an extensible system means adding new classes, methods, functions, or data that encapsulate the new behavior. But because real systems are rarely ideal, you’ll still find yourself needing to make changes to existing code regularly. One of the things that help developers write clean, well-structured, and easily-maintainable code is SOLID principles.
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How to Build Custom Flexible Rest Architecture in the Salesforce
The Classic Salesforce platform is designed to use the MVC pattern for developing applications and customizing existing functionality. The benefits of server rendering are obvious, but we often need more dynamic in the application. In this case, Rest Services will help us. By default, Salesforce has the following capabilities: Rest API Soap API Remote Actions The platform is also known for its limits. In this case — API Usage Limit. We will get rid of the problems and overcome the limits. Solution The solution is to use the standard Visualforce page with a custom controller to get the result of the request. As a result, we have a page with the following contents: 📄 Copy to clipboard 1 2 3 4 5 6 <apex:page controller="GS_RestApiController" action="{!execute}" contenttype="text/javascript" showHeader="false" sidebar="false"> <apex:outputText value="{!response}" escape="false"/> </apex:page> The method execute from the GS_RestApiController controller will be executed when the page is loaded. The result will be bound into the outputText. Controller Code: 📄 Copy to clipboard 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 public class GS_RestApiController { private static final String COMMAND_NAME_PARAM = 'command'; private Map<String, String> commandAliasNameMap = new Map<String, String>{ 'test' => 'FirstTest' }; public String response {get; private set;} public GS_RestApiController() { } public void execute() { this.response = getCommand().execute().toJSON(); } private GS_CommandContainer.GS_Command getCommand() { Map<String, String> params = ApexPages.currentPage().getParameters(); String commandName = params.get(COMMAND_NAME_PARAM); if (commandAliasNameMap.containsKey(commandName)) { commandName = commandAliasNameMap.get(commandName); } params.remove(COMMAND_NAME_PARAM); return GS_CommandFactory.create(commandName, params); } } In the controller, we use the command param to execute the command, and we have the map between the command and its alias if necessary. All commands are stored in container class — GS_CommandContainer 📄 Copy to clipboard 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 public class GS_CommandContainer { public abstract class GS_Command { private Map<String, String> params = new Map<String, String>(); public void setParams(Map<String, String> params) { this.params = params; } public GS_RestResponse execute() { try { Object resultObject = perform(); return new GS_RestResponse(GS_StatusCode.OK, getMessage(), resultObject); } catch (GS_Exception exp) { String message = exp.getMessage() + exp.getStackTraceString(); return new GS_RestResponse(GS_StatusCode.ERROR, message); } catch (Exception exp) { String message = exp.getMessage() + exp.getStackTraceString(); return new GS_RestResponse(GS_StatusCode.ERROR, message); } } public abstract Object perform(); public virtual String getMessage() { return null; } } public class GS_DefaultCommand extends GS_Command { public override Object perform() { return 'This is defult result.'; } public override String getMessage() { return 'This is default message.'; } } Thus, to add a new command, it is necessary simply to extend the base class GS_Command and implement the perform() method where the execution logic will be present. GS_CommandFactory is designed to create an instance of the GS_Command class. 📄 Copy to clipboard 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 public class GS_CommandFactory { private static final String DOT = '.'; private static final String COMMAND_CONTAINER_NAME = 'GS_CommandContainer'; private static final String DEFAULT_COMMAND_NAME = 'GS_DefaultCommand'; private static final String COMMAND_NAME_TEMPLATE = 'GS_{0}Command'; private static final String COMMAND_NAME_TEMPLATE_WITH_CONTAINER = COMMAND_CONTAINER_NAME + DOT + COMMAND_NAME_TEMPLATE; private static final String DEFAULT_COMMAND_NAME_TEMPLATE_WITH_CONTAINER = COMMAND_CONTAINER_NAME + DOT + DEFAULT_COMMAND_NAME; public static GS_CommandContainer.GS_Command create() { Type commandType = Type.forName(DEFAULT_COMMAND_NAME_TEMPLATE_WITH_CONTAINER); GS_CommandContainer.GS_Command command = (GS_CommandContainer.GS_Command)commandType.newInstance(); return command; } public static GS_CommandContainer.GS_Command create(String commandName, Map<String, String> params) { if(String.isBlank(commandName)) { create(); } String commandClassName = String.format(COMMAND_NAME_TEMPLATE_WITH_CONTAINER, new String[] {commandName}); Type commandType = Type.forName(commandClassName); if(commandType == null) { commandType = Type.forName(DEFAULT_COMMAND_NAME_TEMPLATE_WITH_CONTAINER); } GS_CommandContainer.GS_Command command = (GS_CommandContainer.GS_Command)commandType.newInstance(); command.setParams(params); return command; } } It creates an instance of the required command, depending on the given parameter, or creates an instance of the default class if no such command is found. The example of use is quite simple: 📄 Copy to clipboard 1 var result = $.post('{!Page.RestApi}', {command : 'test'}); The result is: 📄 Copy to clipboard 1 {"result":"FirstTestResult + Params : {}","message":"FirstTestMessage","code":200} When you perform a request without any parameters, the default command is executed. The command name must match the COMMAND_NAME_TEMPLATE template described in GS_CommandFactory, and it is also possible to add the alias and command name to the commandAliasNameMap in the GS_RestApiController. From our side, the architecture is convenient and easily extensible. The source code you can find on GitHub. Nowadays, when Lightning Components is became standard for developing UI. It make less sense. But it can help you if you make custom UI with any JS framework (Angular, React, Vue) or you faced with any problem related with AuraEnabled methods.
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How to fix ‘Bad value for restricted picklist field’ error
Users or developers may receive the following error when they attempt to create or update a record in Salesforce: Error: Invalid Data. Review all error messages below to correct your data.‘Bad value for restricted picklist field: PicklistValue’ This error occurs when the picklist field referenced in the error message meets each of the following conditions:
How to merge Accounts in Salesforce
Data quality is one of the most important things you have to watch to get the most out of Salesforce. This helps your sales team to obtain accurate customer data in accordance with various privacy and privacy rules. Salesforce gives you tools for managing duplicates one at a time and across your org, and to track your progress in eliminating duplicates. We will show how to merge Accounts in different interfaces and do not forget about a little Salesforce Hack at the end of the article.
