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61
A static study of java exceptions using jesp
- In International Conference on Compiler Construction
, 2000
"... Abstract. JESP is a tool for statically examining the usage of user thrown exceptions in Java source code. Reported here are the first findings over a dataset of 31 publicly available Java codes, including the JavaSpecs. Of greatest interest to compiler writers are the findings that most Java except ..."
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Cited by 16 (0 self)
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Abstract. JESP is a tool for statically examining the usage of user thrown exceptions in Java source code. Reported here are the first findings over a dataset of 31 publicly available Java codes, including the JavaSpecs. Of greatest interest to compiler writers are the findings that most Java exceptions are thrown across method boundaries, trys and catches occur in equal numbers, finallys are rare, and programs fall into one of two categories, those dominated by throw statements and those dominated by catch statements. The research reported here was supported, in part, by NSF grant CCR-9808607. 2
Object Views: Language Support for Intelligent Object Caching in Parallel and Distributed Computations
- In Proceedings of the 1999 Conference on Object-Oriented Programming Systems, Languages and Applications
, 1999
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Compiler-directed Program-fault Coverage for Highly Available Java Internet Services
- In Proceedings of the International Conference on Dependable Systems and Networks (DSN
, 2003
"... We present a new approach that uses compilerdirected fault-injection for coverage testing of recovery code in Internet services to evaluate their robustness to operating system and I/O hardware faults. We define a set of program-fault coverage metrics that enable quantification of Java catch blocks ..."
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Cited by 14 (5 self)
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We present a new approach that uses compilerdirected fault-injection for coverage testing of recovery code in Internet services to evaluate their robustness to operating system and I/O hardware faults. We define a set of program-fault coverage metrics that enable quantification of Java catch blocks exercised during fault-injection experiments. We use compiler analyses to instrument application code in two ways: to direct fault injection to occur at appropriate points during execution, and to measure the resulting coverage. As a proof of concept for these ideas, we have applied our techniques manually to Muffin, a proxy server; we obtained a high degree of coverage of catch blocks, with, on average, 85% of the expected faults per catch being experienced as caught exceptions.
Dynamic Object Replacement and Implementation-Only Classes
- 6th International Workshop on Component-Oriented Programming (WCOP 2001) at ECOOP 2001
, 2001
"... GILGUL is an extension of the Java programming language that allows for dynamic object replacement without consistency problems. This is possible in a semantically clean way because its model strictly separates the notions of reference and comparison that are usually subsumed in the concept of objec ..."
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Cited by 13 (3 self)
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GILGUL is an extension of the Java programming language that allows for dynamic object replacement without consistency problems. This is possible in a semantically clean way because its model strictly separates the notions of reference and comparison that are usually subsumed in the concept of object identity. Since GILGUL's new operations respect Java's type system, objects can still be replaced only by instances of the same class or any subclasses thereof, but not by instances of any superclass. The concept of implementation-only classes is an extension of the type system that allows classes to be declared that must never be used as types. Consequently, instances of implementation-only classes can always be replaced by instances of their superclasses. This effectively widens the range of both anticipated and unanticipated adaptations.
Declarative Specification of Data-intensive Web sites
, 1999
"... Integrated information systems are often realized as data-intensive Web sites, which integrate data from multiple data sources. We present a system, called Strudel, for specifying and generating data-intensive Web sites. Strudel separates the tasks of accessing and integrating a site's data sou ..."
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Cited by 12 (1 self)
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Integrated information systems are often realized as data-intensive Web sites, which integrate data from multiple data sources. We present a system, called Strudel, for specifying and generating data-intensive Web sites. Strudel separates the tasks of accessing and integrating a site's data sources, building its structure, and generating its HTML representation. Strudel's declarative query language, called StruQL, supports the first two tasks. Unlike ad-hoc database queries, a StruQL query is a software artifact that must be extensible and reusable. To support more modular and reusable site-definition queries, we extend StruQL with functions and describe how the new language, FunStruQL, better supports common site-engineering tasks, such as choosing a strategy for generating the site's pages dynamically and/or statically. To substantiate Strudel's benefits, we describe the re-engineering of a production Web site using FunStruQL and show that the new site is smaller, more reusable, and ...
Scheduling optimization under uncertainty: An alternative approach
- Computers and Chemical Engineering
, 2003
"... The prevalent approach to the treatment of processing time uncertainties in production scheduling problems is through the use of probabilistic models. Apart from requiring detailed information about probability distribution functions, this approach also has the drawback that the computational expens ..."
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The prevalent approach to the treatment of processing time uncertainties in production scheduling problems is through the use of probabilistic models. Apart from requiring detailed information about probability distribution functions, this approach also has the drawback that the computational expense of solving these models is very high. In this work, we present a non-probabilistic treatment of scheduling optimization under uncertainty, based on concepts from fuzzy set theory and interval arithmetic, to describe the imprecision and uncertainty in the task durations. We first provide a brief review on the fuzzy set approach, comparing it with the probabilistic approach. We then present MILP models derived from applying this ap-proach to two different problems- flowshop scheduling and new product development process scheduling. Results indicate that these MILP models are computationally tractable for reason-ably sized problems. We also describe tabu search implementations in order to handle larger problems. 1
Automated and portable native code isolation
- In Proceedings of the 12th International Symposium on Software Reliability Engineering (ISSRE‘01
, 2001
"... The coexistence of programs written in a safe language with user-supplied unsafe (native) code is convenient (it enables direct access to hardware and operating system resources and can improve application performance), but at the same time it is problematic (it leads to undesirable interference wit ..."
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The coexistence of programs written in a safe language with user-supplied unsafe (native) code is convenient (it enables direct access to hardware and operating system resources and can improve application performance), but at the same time it is problematic (it leads to undesirable interference with the language runtime, decreases overall reliability, and lowers debuggability). This work aims at retaining most of the benefits of interfacing a safe language with native code while addressing its problems. It is carried out in the context of the Java ™ Native Interface (JNI). Our approach is to execute the native code in an operating system process different from that of the safe language application. A technique presented in this paper accomplishes this transparently, automatically, and without sacrificing any of the JNI functionality. No changes to the Java virtual machine (JVM™) or its runtime are necessary. The resulting prototype does not depend on a particular implementation of the JVM, and is highly portable across hardware architectures and operating systems. This approach can readily be used to improve reliability of applications consisting of a mix of safe and native code; to enable the execution of user-supplied native code in multitasking systems based on safe languages and in embedded virtual machines; and to facilitate mixed-mode debugging, without the need to re-implement any of the components of the language runtime. The design and implementation of a prototype system, performance implications, and the potential of this architecture are discussed in the paper.
Unsupervised Detection of Anomalous Text
, 2008
"... This thesis describes work on the detection of anomalous material in text without the use of training data. We use the term anomalous to refer to text that is irregular, or deviates significantly from its surrounding context. In this thesis we show that identifying such abnormalities in text can be ..."
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This thesis describes work on the detection of anomalous material in text without the use of training data. We use the term anomalous to refer to text that is irregular, or deviates significantly from its surrounding context. In this thesis we show that identifying such abnormalities in text can be viewed as a type of outlier detection because these anomalies will differ significantly from the writing style in the majority of the data. We consider segments of text which are anomalous with respect to topic (i.e. about a different subject), author (written by a different person), or genre (written for a different audience or from a different source) and experiment with whether it is possible to identify these anomalous segments automatically. Five different innovative approaches to this problem are introduced and assessed using many experiments over large document collections, created to contain randomly inserted anomalous segments. In order to identify anomalies in text successfully, we investigate and evaluate 166 stylistic and linguistic features used to characterize writing, some of which are well-established stylistic determiners, but many of which are original. Using these features with each of our methods, we examine the effect of segment size on our ability to detect anomaly, allowing segments of size 100 words, 500 words and 1000 words. We show substantial improvements over a baseline in all cases for all methods, and identify a novel method which performs consistently better than others and the features that contribute most to unsupervised anomaly detection.
Management of Intelligent Learning Agents in Distributed Data Mining Systems
, 1999
"... Data mining systems aim to discover patterns and extract useful information from facts recorded in databases. One means of acquiring knowledge from databases is to apply various machine learning algorithms that compute descriptive representations of the data as well as patterns that may be exhibit ..."
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Cited by 7 (2 self)
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Data mining systems aim to discover patterns and extract useful information from facts recorded in databases. One means of acquiring knowledge from databases is to apply various machine learning algorithms that compute descriptive representations of the data as well as patterns that may be exhibited in the data. Most of
Object Identity and Dynamic Recomposition of Components
- in: TOOLS Europe 2001. Proceedings, IEEE Computer
, 2000
"... Dynamic recomposition of components in a program imposes new requirements on the expressive power of object-oriented programming languages. For example, the replacement of a component with another reveals consistency problems stemming from the fact that the concept of object identity tries to fulfil ..."
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Cited by 7 (4 self)
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Dynamic recomposition of components in a program imposes new requirements on the expressive power of object-oriented programming languages. For example, the replacement of a component with another reveals consistency problems stemming from the fact that the concept of object identity tries to fulfil the distinct purposes of reference and comparison. By clearly separating the two notions and providing means to manipulate them independently, the consistency problems can completely be avoided.
