Custom Apex error logging sample.

apex-error-logger.md

Custom Apex Error Logger

Implement a custom error logging framework from scratch.

Assumes a Custom Object ErrorLog exists.

LoggableException.java

public virtual class LoggableException extends Exception {
	private ErrorLog__c errorLog;
	private List<ExceptionLog__c> exceptionLogs;
	private List<RowLog__c> rowLogs;
	private List<ServiceLog__c> serviceLogs;

	public void init(Exception exc) {
		errorLog = new ErrorLog__c();
		exceptionLogs = new List<ExceptionLog__c>();
		rowLogs = new List<RowLog__c>();
		serviceLogs = new List<ServiceLog__c>();

		// initialize logger with the first exception
	}

	public void addException(Exception exc) {
		// add an exception to the error log
	}

	public void flush() {
		// commit all data to salesforce
	}
}

MyBusinessLayer.java

public class MyBusinessLayer {
  MyDataLayer data = new MyDataLayer();
  public void doThing () {
    Contact newContact = newContact(Id = '00300000000000a');
    try {
      data.insertContact(newContact);
    } catch(LoggableException lexc) {
      MyCustomException myexc = new MyCustomException(lexc);
      lexc.addException(myexc);
      throw myexc;
    }
  }
}

MyDataLayer.java

public class MyDataLayer {
  public void insertContact (Contact newContact) {
    try {
      insert newContact;
    } catch (DmlException dmle) {
      // Catch and Handle a DML Exception
      // Record it to an SObject and attach it to my custom exception
      LoggableException loggable = exc.init(dmle);
      // Rethrow the exception so the Application and/or Presentation Layers can handle it.
      // Upper layers in the stack may get and add more context to the Error Log 
      // as the exception bubbles up the stack.
      throw loggable;
    }
  }
}

MyException.java

public class MyException extends LoggableException {}