Oracle International Corporation

Sun Microsystems, Inc.

Oracle America, Inc.

Oracle America, Inc. Formerly Sun Microsystems, Inc.

Joseph D Darcy

Alexander R Buckley

Maurizio Cimadamore

Jonathan J Gibbons

Jan Lahoda

Scott Seligman

Brian Goetz

John Robert Rose

Gilad Bracha

Stuart Warren Marks

Peter Von Der Ahe

Vicente A Romero Zaldivar

Olivier Lagneau

Magnus Ihse Bursie

Cross-compiling, by a multi-version compiler, may produce complied code targeted to a specified release version of a programming platform supported by the compiler. The specified version may be different from a default version of the programming platform targeted by the compiler. Thus, the multi-version compiler may cross-compile source code to generate compiled code for different versions of the programming platform. A developer may specify the target version using a single compiler option and the compiler may, in response, cross-compile for the target version without requiring any additional options to be configured by the user. The multi-version compiler may include library data regarding multiple versions of the programming platform, preventing a developer from having to locate and provide the necessary library data for each targeted version.

Multi-platform compiling

Annotation processors defined by a module of a module system are used for processing annotations. Annotation processors defined by a module of a module system may be used with annotation processors defined by non-module code. A predefined deterministic process is used to select annotation processors for processing annotations. The predefined deterministic process imposes an order for searching and/or using annotation processors.

Using annotation processors defined by modules with annotation processors defined by non-module code

Described herein are systems and methods for conversion of numeric values between different number base formats, for use with software applications. In accordance with an embodiment, an integral part of a passed floating-point numeric value in a source number base (e.g., binary) format is isolated and converted to an integer. A fractional part of the numeric value is also isolated and converted to an integer, while limiting the isolation and conversion of the fractional part to a required precision or number of digits, depending on the particular requirements of a software application. The fractional part can be rounded, including determining an exact roundoff as appropriate, and if necessary propagating the rounding to the integral part. Digits from the resulting integers representing the integral and fractional parts can then be collected and used to prepare a representation of the original numeric value in a target number base (e.g., decimal) format.

System and method for conversion of numeric values between different number base formats, for use with software applications

A compiler may receive source code including two user source code blocks, each capable of throwing an exception. The received source code may be associated with a policy that discards a pending exception when a subsequent exception occurs. The compiler may transform the source code such that it allows for a propagation policy that supports multiple exceptions. The transformed source code may be executed in an execution environment. Upon execution of the transformed code, a pending exception may be propagated out and a later-in-time exception may be stored.

Error propagation

The disclosed embodiments provide a system that facilitates the development and compilation of a software program. During operation, the system provides, in a programming language platform associated with source code for the software program, an indicator for a resource with a close method that does not complete erroneously. Next, the system enables use of the indicator with a resource-management statement in the source code, wherein the indicator facilitates omission of an exception-handling construct for the resource-management statement.

Indicators for resources with close methods that do not complete erroneously in software programs

The disclosed embodiments provide a system that facilitates the development and compilation of a software program. During operation, the system provides, in a programming language platform associated with source code for the software program, an indicator for a resource with an idempotent close method. Next, the system enables use of the indicator with a resource-management statement in the source code, wherein the indicator facilitates the use of a wrapped resource in the resource-management statement.

Indicators for resources with idempotent close methods in software programs

A tool, such as a compiler or an interpreter, receives program source code and determines that the code includes an operation for which type conversion is permitted on an operand. The tool determines a source type of the operand, and a target type to which the operand is to be converted. In response to determining that the source type is a reference type and the target type is a primitive type, the tool generates a set of instructions to (a) determine whether, at run time, in accordance with a class definition of the reference type, a value of the target primitive type can be obtained via one or more method invocations on the operand (b) if such a value can be obtained, obtain the value and assign the value to a result of the operation and (c) if such a value cannot be obtained, generate an error indication.

Efficient and expansive conversions between reference and primitive

One embodiment of the present invention provides a system that characterizes content in object code. During operation, the system receives the source code of a program. The system also receives one or more pieces of object code of the program, or creates one or more pieces of object code from the source code. Next, the system identifies a construct in the object code. The system then determines whether the construct is physically present in the source code. If the construct is not physically present, the system determines whether the construct is logically present in the source code, wherein a construct is logically present if it is required by the programming language. If so, the system sets a construct flag to indicate that the construct is 'synthesized.' However, if not, the system sets the construct flag to indicate that the construct is 'synthetic.' Finally, the construct flag is made available to a reflective API.

Characterizing artificiality in object code

A compiler receives source code for a program and determines that the code includes a declaration expression and an initialization expression in an assignment context. The declaration expression introduces a variable and specifies part of a parameterized type for the variable but not another part of the parameterized type. A parameterized type may include a ground type part and one or more type arguments; in a declaration expression, the specified part of the parameterized type may include a ground type and the unspecified part may include one or more of the type arguments. The initialization expression specifies an initial value for the variable, where the value has a parameterized type. The assignment context associates the declared variable with the initial value. The compiler infers the type for the variable based at least on the part specified in the declaration expression and on the type specified by the initialization expression.

Type inference of partially-specified parameterized types

Various embodiments herein include one or more of systems, methods, software, and/or data structures to implement a multi-way branch statement in a computer programming language. The multi-way branch statement may include a plurality of case labels each having a non-primitive data type (e.g., strings) and being associated with a block of code to be executed dependent upon a control variable that also has a non-primitive data type. The implementation may include encoding the case labels for the multi-way branch statement as a binary decision diagram (BDD), such as a zero-suppressed binary decision diagram (ZDD), wherein the control variable for the multi-way branch statement may be compared with the case labels by stepping through the BDD. The BDD may include identifiers that provide information regarding which of the case labels is matched by the control variable, such that an appropriate code block may be executed.

Encoding switch on ordered universes with binary decision diagrams

A method for compiling source code, involving: obtaining a statement of the source code comprising a method call, where the source code is composed in a statically-typed programming language; determining whether the method call is a dynamic method call; upon determining that the method call is a dynamic method call, compiling a dynamic method invocation without performing type checking on the method call; upon determining that the method call is not a dynamic method call: performing type checking on the method call, selecting a target method to invoke, and compiling a static method invocation to invoke the target method.

Method and system for compiling a dynamically-typed method invocation in a statically-typed programming language

Various embodiments herein include one or more of systems, methods, software, and/or data structures to implement a 'pluperfect' hash function. Generally, a pluperfect hash function is a hash function that maps distinct elements in a set S to distinct hash values H with no collisions (i.e., perfect hash function) and also includes an additional constraint that the hash function does not map other elements outside the set S into the set of distinct hash values H. In some example embodiments, pluperfect hash functions are used to implement a multi-way branch statement in a computer programming language. The implementation may include generating hash values for each of the case labels of the branch statement according to a pluperfect hash function.

Pluperfect hashing

A technique in accordance with one embodiment of the present invention provides introspection support for anonymous and local classes. As a result of the technique, an enclosing class that defines a generic type variable that is not defined within a local or anonymous class that refers to the generic type variable can be determined. According to one embodiment of the invention, when a compiler determines that a particular class is a local or anonymous class, the compiler emits, into the particular class' binary class file, information that indicates which class encloses the particular class. In response to the invocation of a method (described herein) relative to a reflective proxy that corresponds to an enclosed class, information that identifies an enclosing class that encloses the enclosed class is returned. This is so even if the enclosed class is a local or anonymous class.

Introspection support for local and anonymous classes

Methods for discovering and accessing annotation processors are provided. The method initiates with identifying an annotation present in a source file and identifying factories available for processing annotations. The method includes determining annotations supported by each of the available factories. Then, one of the available factories is assigned to process the annotation based on the annotation present in the source file being supported by the one of the available factories. A computer readable medium is also provided.

Annotation processor discovery

In accordance with one embodiment of the present invention, there is provided a technique for supporting introspection of generic types while maintaining migration compatibility. According to one aspect of this technique, in response to an invocation of a programmatic method of a reflective proxy, a string representation of a program element that corresponds to the reflective proxy is generated. The string representation contains information that is based on formal type parameters that are associated with the declaration of the generic type that is associated with the program element. According to another aspect, the programmatic method described above differs from another existing programmatic method 'toString( )' that generates a string representation that does not indicate generic type-specific information. Thus, programs that depend upon the existing implementation of the 'toString( )' method may continue to use it. According to one embodiment, the &#x201c;toString( )&#x201d; method is unchanged, but a method &#x201c;toGenericString( )&#x201d; is also implemented.

Growing community of inventors

Mountain View, CA, United States of America

Joseph D Darcy