Package org.intellij.lang.annotations

Annotation Type Flow

  • @Retention(CLASS)
@Target({PARAMETER,METHOD})
public @interface Flow
    This annotation assists the 'Data flow to this' feature by describing data flow from the method parameter to the corresponding container (e.g. ArrayList.add(item)) or from the container to the method return value (e.g. Set.toArray()) or between method parameters (e.g. System.arraycopy(array1, 0, array2, length))

    • Optional Element Summary

      Optional Elements 
      Modifier and Type Optional Element Description
      java.lang.String source
      Denotes the source of the data flow.
      Allowed values are:
      THIS_SOURCE - Means that the data flows from this container.
      E.g.
      boolean sourceIsContainer
      true if the data source is container and we should track not the expression but its contents.
      E.g.
      java.lang.String target
      Denotes the destination of the data flow.
      Allowed values are:
      THIS_TARGET - Means that the data flows inside this container (of the class the annotated method belongs to).
      E.g.
      boolean targetIsContainer
      true if the data target is container and we should track not the expression but its contents.
      E.g.

    • Field Detail

      • DEFAULT_SOURCE

        static final java.lang.String DEFAULT_SOURCE

      • THIS_SOURCE

        static final java.lang.String THIS_SOURCE

      • DEFAULT_TARGET

        static final java.lang.String DEFAULT_TARGET

      • RETURN_METHOD_TARGET

        static final java.lang.String RETURN_METHOD_TARGET

      • THIS_TARGET

        static final java.lang.String THIS_TARGET

    • Element Detail

      • source

        java.lang.String source
        Denotes the source of the data flow.
        Allowed values are:
        • THIS_SOURCE - Means that the data flows from this container.
          E.g. annotation for java.util.List method get(index) means the method reads contents of list and returns it.
          @Flow(source = THIS_SOURCE) T get(int index);
        • this.Field name - means that the data flows from this container some (synthetic) field.
          E.g. annotation for java.util.Map.keySet() method here means that it returns data from the map from the field named "keys".
          @Flow(source = "this.keys") Set<K> keySet();
        By default, the source() value is:
        • THIS_SOURCE if the method was annotated, e.g.
          @Flow(sourceIsContainer=true, targetIsContainer=true) Object[] Collection.toArray()
          Here the annotation tells us that java.util.Collection.toArray() method
          reads the contents of this collection (source=THIS_SOURCE by default) and passes it outside.
        • Corresponding argument if the method parameter was annotated, e.g.
          void List.add(@Flow(targetIsContainer=true) E item)
          Here the annotation tells us that java.util.List.add(E item) method
          takes the argument (source="item" by default) and passes it to this collection.
        Default:
        "The method argument (if parameter was annotated) or this container (if instance method was annotated)"

      • sourceIsContainer

        boolean sourceIsContainer
        true if the data source is container and we should track not the expression but its contents.
        E.g. the java.util.ArrayList constructor takes the collection and stores its contents:
        ArrayList(
        @Flow(sourceIsContainer=true, targetIsContainer=true) Collection<? extends E> collection
        )
        By default it's false.
        Default:
        false

      • target

        java.lang.String target
        Denotes the destination of the data flow.
        Allowed values are:
        • THIS_TARGET - Means that the data flows inside this container (of the class the annotated method belongs to).
          E.g. annotation for java.util.List method add(element) means the method takes the argument and passes it to this collection.
          boolean add(@Flow(target=THIS_TARGET, targetIsContainer=true) E element);
        • Parameter name - means the data flows to this parameter.
          E.g.
          void arraycopy(@Flow(sourceIsContainer=true, target="dest", targetIsContainer=true) Object src, int srcPos, Object dest, int destPos, int length)
          means that java.lang.System.arraycopy() method takes its first argument and passes it to the "dest" parameter.
        • this.Field name - means that the data flows to this container in some (synthetic) field.
          E.g. annotation for java.util.Map.put(key, value) method here means that it takes the argument 'key' and stores the data in some (hidden) field named "keys".
          V put(@Flow(target = "this.keys", targetIsContainer=true) K key, V value);
        By default, the target() value is:
        • THIS_TARGET if the parameter was annotated, e.g.
          void List.set(int index, @Flow(targetIsContainer=true) E element)
          Here the annotation tells us that java.util.List.set(index, element) method
          reads its second argument 'element' and passes it to this collection (target=THIS_TARGET by default).
        • RETURN_METHOD_TARGET if the method was annotated, e.g.:
          @Flow(sourceIsContainer=true) E List.remove(int index)
          Here the annotation tells us that java.util.List.remove(int index) method
          returns the data from its collection (target=RETURN_METHOD_TARGET by default).
        Default:
        "This container (if the parameter was annotated) or the return value (if instance method was annotated)"

      • targetIsContainer

        boolean targetIsContainer
        true if the data target is container and we should track not the expression but its contents.
        E.g. the java.lang.System.arraycopy() method parameter 'dest' is actually an array:
        void arraycopy(@Flow(sourceIsContainer=true, target="dest", targetIsContainer=true) Object src, int srcPos, Object dest, int destPos, int length)
        By default it's false.
        Default:
        false