Rules that flag suboptimal code.
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AvoidDebugStatements

Since: PMD 6.36.0

Priority: Medium (3)

Debug statements contribute to longer transactions and consume Apex CPU time even when debug logs are not being captured.

When possible make use of other debugging techniques such as the Apex Replay Debugger and Checkpoints that could cover most use cases.

For other valid use cases that the statement is in fact valid make use of the @SuppressWarnings annotation or the //NOPMD comment.

This rule is defined by the following XPath expression:

//MethodCallExpression[lower-case(@FullMethodName)='system.debug']

Example(s):

public class Foo {
    public void bar() {
        Account acc = [SELECT Name, Owner.Name FROM Account LIMIT 1];
        System.debug(accs); // will get reported
    }

    @SuppressWarnings('PMD.AvoidDebugStatements')
    public void baz() {
        try {
            Account myAccount = bar();
        } catch (Exception e) {
            System.debug(LoggingLevel.ERROR, e.getMessage()); // good to go
        }
    }
}

Use this rule by referencing it:

<rule ref="category/apex/performance.xml/AvoidDebugStatements" />

AvoidDmlStatementsInLoops

Deprecated

Since: PMD 5.5.0

Priority: Medium (3)

Avoid DML statements inside loops to avoid hitting the DML governor limit. Instead, try to batch up the data into a list and invoke your DML once on that list of data outside the loop.

This rule is deprecated and will be removed with PMD 7.0.0. The rule is replaced by the more general rule OperationWithLimitsInLoop.

This rule is defined by the following Java class: net.sourceforge.pmd.lang.apex.rule.performance.AvoidDmlStatementsInLoopsRule

Example(s):

public class Something {
    public void foo() {
        for (Integer i = 0; i < 151; i++) {
            Account account;
            // ...
            insert account;
        }
    }
}

Use this rule by referencing it:

<rule ref="category/apex/performance.xml/AvoidDmlStatementsInLoops" />

AvoidSoqlInLoops

Deprecated

Since: PMD 5.5.0

Priority: Medium (3)

New objects created within loops should be checked to see if they can created outside them and reused.

This rule is deprecated and will be removed with PMD 7.0.0. The rule is replaced by the more general rule OperationWithLimitsInLoop.

This rule is defined by the following Java class: net.sourceforge.pmd.lang.apex.rule.performance.AvoidSoqlInLoopsRule

Example(s):

public class Something {
    public static void main( String as[] ) {
        for (Integer i = 0; i < 10; i++) {
            List<Account> accounts = [SELECT Id FROM Account];
        }
    }
}

Use this rule by referencing it:

<rule ref="category/apex/performance.xml/AvoidSoqlInLoops" />

AvoidSoslInLoops

Deprecated

Since: PMD 6.0.0

Priority: Medium (3)

Sosl calls within loops can cause governor limit exceptions.

This rule is deprecated and will be removed with PMD 7.0.0. The rule is replaced by the more general rule OperationWithLimitsInLoop.

This rule is defined by the following Java class: net.sourceforge.pmd.lang.apex.rule.performance.AvoidSoslInLoopsRule

Example(s):

public class Something {
    public static void main( String as[] ) {
        for (Integer i = 0; i < 10; i++) {
            List<List<SObject>> searchList = [FIND 'map*' IN ALL FIELDS RETURNING Account (Id, Name), Contact, Opportunity, Lead];
        }
    }
}

Use this rule by referencing it:

<rule ref="category/apex/performance.xml/AvoidSoslInLoops" />

OperationWithLimitsInLoop

Since: PMD 6.29.0

Priority: Medium (3)

Database class methods, DML operations, SOQL queries, SOSL queries, Approval class methods, Email sending, async scheduling or queueing within loops can cause governor limit exceptions. Instead, try to batch up the data into a list and invoke the operation once on that list of data outside the loop.

This rule is defined by the following Java class: net.sourceforge.pmd.lang.apex.rule.performance.OperationWithLimitsInLoopRule

Example(s):

public class Something {
    public void databaseMethodInsideOfLoop(List<Account> accounts) {
        for (Account a : accounts) {
            Database.insert(a);
        }
    }

    public void dmlInsideOfLoop() {
        for (Integer i = 0; i < 151; i++) {
            Account account;
            // ...
            insert account;
        }
    }

    public void soqlInsideOfLoop() {
        for (Integer i = 0; i < 10; i++) {
            List<Account> accounts = [SELECT Id FROM Account];
        }
    }

    public void soslInsideOfLoop() {
        for (Integer i = 0; i < 10; i++) {
            List<List<SObject>> searchList = [FIND 'map*' IN ALL FIELDS RETURNING Account (Id, Name), Contact, Opportunity, Lead];
        }
    }

    public void messageInsideOfLoop() {
        for (Integer i = 0; i < 10; i++) {
            Messaging.SingleEmailMessage email = new Messaging.SingleEmailMessage();
            Messaging.sendEmail(new Messaging.SingleEmailMessage[]{email});
        }
    }

    public void approvalInsideOfLoop(Account[] accs) {
        for (Integer i = 0; i < 10; i++) {
            Account acc = accs[i];
            Approval.ProcessSubmitRequest req = new Approval.ProcessSubmitRequest();
            req.setObjectId(acc.Id);
            Approval.process(req);
            Approval.lock(acc);
            Approval.unlock(acc);
        }
    }

    public void asyncInsideOfLoop() {
        for (Integer i = 0; i < 10; i++) {
            System.enqueueJob(new MyQueueable());
            System.schedule('x', '0 0 0 1 1 ?', new MySchedule());
            System.scheduleBatch(new MyBatch(), 'x', 1);
        }
    }
}

Use this rule by referencing it:

<rule ref="category/apex/performance.xml/OperationWithLimitsInLoop" />