Class ElementSource

java.lang.Object
com.google.inject.spi.ElementSource

public final class ElementSource extends Object
Contains information about where and how an element was bound.

The declaring source refers to a location in source code that defines the Guice element. For example, if the element is created from a method annotated by @Provides, the declaring source of element would be the method itself.

The getStackTrace() refers to the sequence of calls ends at one of Binder bindXXX() methods and eventually defines the element. Note that getStackTrace() lists StackTraceElements in reverse chronological order. The first element (index zero) is the last method call and the last element is the first method invocation. By default, the stack trace is not collected. The default behavior can be changed by setting the guice_include_stack_traces flag value. The value can be either OFF, ONLY_FOR_DECLARING_SOURCE or COMPLETE. Note that collecting stack traces for every binding can cause a performance hit when the injector is created.

The sequence of class names of modules involved in the element creation can be retrieved by getModuleClassNames(). Similar to getStackTrace(), the order is reverse chronological. The first module (index 0) is the module that installs the element. The last module is the root module.

In order to support the cases where a Guice element is created from another Guice element (original) (e.g., by Element.applyTo(com.google.inject.Binder)), it also provides a reference to the original element source (getOriginalElementSource()).

Since:
4.0
  • Field Details

    • originalElementSource

      final ElementSource originalElementSource
      The source of element that this element created from (if there is any), otherwise null.
    • moduleSource

      final ModuleSource moduleSource
      The source of module creates the element.
    • partialCallStack

      The partial call stack that starts at the last module configure(Binder) call. The value is empty if stack trace collection is off.
    • declaringSource

      final Object declaringSource
      Refers to a single location in source code that causes the element creation. It can be any object such as Constructor, Method, Field, StackTraceElement, etc. For example, if the element is created from a method annotated by @Provides, the declaring source of element would be the method itself.
  • Constructor Details

    • ElementSource

      ElementSource(ElementSource originalSource, Object declaringSource, ModuleSource moduleSource, StackTraceElement[] partialCallStack)
      Creates a new from the given parameters.
      Parameters:
      originalElementSource - The source of element that this element created from (if there is any), otherwise null.
      declaringSource - the source (in)directly declared the element.
      moduleSource - the moduleSource when the element is bound
      partialCallStack - the partial call stack from the top module to where the element is bound
  • Method Details

    • getOriginalElementSource

      public ElementSource getOriginalElementSource()
      Returns the ElementSource of the element this was created or copied from. If this was not created or copied from another element, returns null.
    • getDeclaringSource

      public Object getDeclaringSource()
      Returns a single location in source code that defines the element. It can be any object such as Constructor, Method, Field, StackTraceElement, etc. For example, if the element is created from a method annotated by @Provides, the declaring source of element would be the method itself.
    • getModuleClassNames

      public List<String> getModuleClassNames()
      Returns the class names of modules involved in creating this Element. The first element (index 0) is the class name of module that defined the element, and the last element is the class name of root module.
    • getModuleConfigurePositionsInStackTrace

      public List<Integer> getModuleConfigurePositionsInStackTrace()
      Returns the position of configure(Binder) method call in the stack trace for modules that their classes returned by getModuleClassNames(). For example, if the stack trace looks like the following:
      1. Binder.bind()
      2. ModuleTwo.configure()
      3. Binder.install()
      4. ModuleOne.configure()
      5. {@code theRest(). </ol> <p>1 and 3 are returned. <p>In the cases where stack trace is not available (i.e., the stack trace was not collected), it returns -1 for all module positions.
    • getStackTrace

      public StackTraceElement[] getStackTrace()
      Returns the sequence of method calls that ends at one of Binder bindXXX() methods and eventually defines the element. Note that getStackTrace() lists StackTraceElements in reverse chronological order. The first element (index zero) is the last method call and the last element is the first method invocation. In the cases where stack trace is not available (i.e.,the stack trace was not collected), it returns an empty array.
    • toString

      public String toString()
      Returns getDeclaringSource().toString() value.
      Overrides:
      toString in class Object