Package com.google.gwt.core.ext.typeinfo

Class TypeOracle

java.lang.Object
com.google.gwt.core.ext.typeinfo.TypeOracle
public abstract class TypeOracle extends Object
Provides type-related information about a set of source files.

All type objects exposed, such as JClassType and others, have a stable identity relative to this type oracle instance. Consequently, you can reliably compare object identity of any objects this type oracle produces. For example, the following code relies on this stable identity guarantee: 

 JClassType o = typeOracle.getJavaLangObject();
 JClassType s1 = typeOracle.getType("java.lang.String");
 JClassType s2 = typeOracle.getType("java.lang.String");
 assert (s1 == s2);
 assert (o == s1.getSuperclass());
 JParameterizedType ls = typeOracle.parse("java.util.List<java.lang.String>");
 assert (ls.getTypeArgs()[0] == s1);

  • Constructor Details

    • TypeOracle

      public TypeOracle()

  • Method Details

    • sort

      public static void sort(JClassType[] types)
      Convenience method to sort class types in a consistent way. Note that the order is subject to change and is intended to generate an "aesthetically pleasing" order rather than a computationally reliable order.

    • sort

      public static void sort(JConstructor[] ctors)
      Convenience method to sort constructors in a consistent way. Note that the order is subject to change and is intended to generate an "aesthetically pleasing" order rather than a computationally reliable order.

    • sort

      public static void sort(JField[] fields)
      Convenience method to sort fields in a consistent way. Note that the order is subject to change and is intended to generate an "aesthetically pleasing" order rather than a computationally reliable order.

    • sort

      public static void sort(JMethod[] methods)
      Convenience method to sort methods in a consistent way. Note that the order is subject to change and is intended to generate an "aesthetically pleasing" order rather than a computationally reliable order.

    • findPackage

      public abstract JPackage findPackage(String pkgName)
      Attempts to find a package by name. All requests for the same package return the same package object.
      Returns:
      null if the package could not be found

    • findType

      public abstract JClassType findType(String name)
      Finds a class or interface given its fully-qualified name.
      Parameters:
      name - fully-qualified class/interface name - for nested classes, use its source name rather than its binary name (that is, use a "." rather than a "$")
      Returns:
      null if the type is not found

    • findType

      public abstract JClassType findType(String pkgName, String typeName)
      Finds a type given its package-relative name. For nested classes, use its source name rather than its binary name (that is, use a "." rather than a "$").
      Returns:
      null if the type is not found

    • getArrayType

      public abstract JArrayType getArrayType(JType componentType)
      Gets the type object that represents an array of the specified type. The returned type always has a stable identity so as to guarantee that all calls to this method with the same argument return the same object.
      Parameters:
      componentType - the component type of the array, which can itself be an array type
      Returns:
      a type object representing an array of the component type

    • getJavaLangObject

      public abstract JClassType getJavaLangObject()
      Gets a reference to the type object representing java.lang.Object.

    • getOrCreatePackage

      public abstract JPackage getOrCreatePackage(String name)
      Ensure that a package with the specified name exists as well as its parent packages.

    • getPackage

      public abstract JPackage getPackage(String pkgName) throws NotFoundException
      Gets a package by name. All requests for the same package return the same package object.
      Returns:
      the package object associated with the specified name
      Throws:
      NotFoundException - if getOrCreatePackage hasn't been called for this package or any child packages

    • getPackages

      public abstract JPackage[] getPackages()
      Gets an array of all packages known to this type oracle.
      Returns:
      an array of packages, possibly of zero-length

    • getParameterizedType

      public abstract JParameterizedType getParameterizedType(JGenericType genericType, JClassType enclosingType, JClassType[] typeArgs)
      Gets the parameterized type object that represents the combination of a specified raw type and a set of type arguments. The returned type always has a stable identity so as to guarantee that all calls to this method with the same arguments return the same object.
      Parameters:
      genericType - a generic base class
      enclosingType -
      typeArgs - the type arguments bound to the specified generic type
      Returns:
      a type object representing this particular binding of type arguments to the specified generic
      Throws:
      IllegalArgumentException - if the parameterization of a non-static member type does not specify an enclosing type or if not enough arguments were specified to parameterize the generic type
      NullPointerException - if genericType is null

    • getParameterizedType

      public abstract JParameterizedType getParameterizedType(JGenericType genericType, JClassType[] typeArgs)
      Gets the parameterized type object that represents the combination of a specified raw type and a set of type arguments. The returned type always has a stable identity so as to guarantee that all calls to this method with the same arguments return the same object.
      Parameters:
      genericType - a generic base class
      typeArgs - the type arguments bound to the specified generic type
      Returns:
      a type object representing this particular binding of type arguments to the specified generic
      Throws:
      IllegalArgumentException - if the generic type is a non-static member type or if not enough arguments were specified to parameterize the generic type
      NullPointerException - if genericType is null

    • getSingleJsoImpl

      public abstract JClassType getSingleJsoImpl(JClassType intf)
      Returns the single implementation type for an interface returned via getSingleJsoImplInterfaces() or null if no JSO implementation is defined.

    • getSingleJsoImplInterfaces

      public abstract Set<? extends JClassType> getSingleJsoImplInterfaces()
      Returns an unmodifiable, live view of all interface types that are implemented by exactly one JSO subtype.

    • getType

      public abstract JClassType getType(String name) throws NotFoundException
      Finds a type given its fully qualified name. For nested classes, use its source name rather than its binary name (that is, use a "." rather than a "$").
      Returns:
      the specified type
      Throws:
      NotFoundException

    • getType

      public abstract JClassType getType(String pkgName, String topLevelTypeSimpleName) throws NotFoundException
      Finds a type given its package-relative name. For nested classes, use its source name rather than its binary name (that is, use a "." rather than a "$").
      Returns:
      the specified type
      Throws:
      NotFoundException

    • getTypes

      public abstract JClassType[] getTypes()
      Gets all types, both top-level and nested.
      Returns:
      an array of types, possibly of zero length

    • getWildcardType

      public abstract JWildcardType getWildcardType(JWildcardType.BoundType boundType, JClassType typeBound)

    • parse

      public abstract JType parse(String type) throws TypeOracleException
      Parses the string form of a type to produce the corresponding type object. The types that can be parsed include primitives, class and interface names, simple parameterized types (those without wildcards or bounds), and arrays of the preceding.

      Examples of types that can be parsed by this method.

      • int
      • java.lang.Object
      • java.lang.String[]
      • char[][]
      • void
      • List<Shape>
      • List<List<Shape>>

      Parameters:
      type - a type signature to be parsed
      Returns:
      the type object corresponding to the parse type
      Throws:
      TypeOracleException