Tooling API Usage

1public class YourClass {
2    public void updateAccount(Account acc, String value) {
3        acc.yourField__c = value;
4        update(acc);
5    }
6}

In the output of a MetadataComponentDependency query, the Apex class is represented as a metadata component (the component doing the referencing, represented by MetadataComponent* field values). The custom field is represented as a referenced metadata component (represented by RefMetadataComponent* field values). Each row in the output shows a directional dependency from one metadata component (such as YourClass) to one of the metadata components that it references (such as yourField).

1public class ClassA {
2    public ClassB newB() {
3        return new ClassB();
4    }
5}

1public class ClassB {
2    public ClassA newA() {
3        return new ClassA();
4    }
5}

In all but the simplest orgs, MetadataComponentDependency queries return a huge number of rows. It can be useful to limit the scope of your requests by type, name, or ID, to help isolate dependencies on specific components.

1SELECT MetadataComponentName, MetadataComponentType
2    FROM MetadataComponentDependency
3    WHERE RefMetadataComponentType = 'ApexClass'

1SELECT MetadataComponentName, MetadataComponentType
2    FROM MetadataComponentDependency
3    WHERE RefMetadataComponentId = yourFieldId