E. Nakagawa, Milena Guessi, J. Maldonado, Daniel Feitosa, F. Oquendo
Reference architectures have emerged as a special type of software architecture that achieves well-recognized understanding of specific domains, promoting reuse of design expertise and facilitating the development, standardization, and evolution of software systems. Because of their advantages, several reference architectures have been proposed and have been also successfully used, including in the industry. However, the most of these architectures are still built using an ad-hoc approach, lacking of a systematization to their construction. If existing, these approaches could motivate and promote the building of new architectures and also support evolution of existing ones. In this scenario, the main contribution of this paper is to present the evolution of ProSA-RA, a process that systematizes the design, representation, and evaluation of reference architectures. ProSA-RA has been already applied in the establishment of reference architectures for different domains and this experience was used to evolve our process. In this paper, we illustrate an application of ProSA-RA in the robotics domain. Results achieved through the use of ProSA-RA have showed us that it is a viable, efficient process and, as a consequence, it could contribute to the reuse of knowledge in several applications domains, by promoting the establishment of new reference architectures.
{"title":"Consolidating a Process for the Design, Representation, and Evaluation of Reference Architectures","authors":"E. Nakagawa, Milena Guessi, J. Maldonado, Daniel Feitosa, F. Oquendo","doi":"10.1109/WICSA.2014.25","DOIUrl":"https://doi.org/10.1109/WICSA.2014.25","url":null,"abstract":"Reference architectures have emerged as a special type of software architecture that achieves well-recognized understanding of specific domains, promoting reuse of design expertise and facilitating the development, standardization, and evolution of software systems. Because of their advantages, several reference architectures have been proposed and have been also successfully used, including in the industry. However, the most of these architectures are still built using an ad-hoc approach, lacking of a systematization to their construction. If existing, these approaches could motivate and promote the building of new architectures and also support evolution of existing ones. In this scenario, the main contribution of this paper is to present the evolution of ProSA-RA, a process that systematizes the design, representation, and evaluation of reference architectures. ProSA-RA has been already applied in the establishment of reference architectures for different domains and this experience was used to evolve our process. In this paper, we illustrate an application of ProSA-RA in the robotics domain. Results achieved through the use of ProSA-RA have showed us that it is a viable, efficient process and, as a consequence, it could contribute to the reuse of knowledge in several applications domains, by promoting the establishment of new reference architectures.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116353407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Most current literature on Software Architecture Knowledge Management (AKM) reports research aimed at developing AKM approaches or identifying challenges in and potential solutions to AKM. However, there has been little effort aimed at empirically studying and describing how AKM is practiced in real-world projects. This paper reports a study aimed at empirically understanding how AKM is currently practiced in industry. Our findings are based on a systematic and rigorous analysis of reports of AKM practices in 29 industrial projects.
{"title":"Empirical Study of Architectural Knowledge Management Practices","authors":"M. Galster, M. Babar","doi":"10.1109/WICSA.2014.28","DOIUrl":"https://doi.org/10.1109/WICSA.2014.28","url":null,"abstract":"Most current literature on Software Architecture Knowledge Management (AKM) reports research aimed at developing AKM approaches or identifying challenges in and potential solutions to AKM. However, there has been little effort aimed at empirically studying and describing how AKM is practiced in real-world projects. This paper reports a study aimed at empirically understanding how AKM is currently practiced in industry. Our findings are based on a systematic and rigorous analysis of reports of AKM practices in 29 industrial projects.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130754506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Energy efficiency is a primary concern for the ICT sector. In particular, the widespread adoption of cloud computing technologies has drawn attention to the massive energy consumption of data centers. Although hardware constantly improves with respect to energy efficiency, this should also be a main concern for software. In previous work we analyzed the literature and elicited a set of techniques for addressing energy efficiency in cloud-based software architectures. In this work we codified these techniques in the form of Green Architectural Tactics. These tactics will help architects extend their design reasoning towards energy efficiency and to apply reusable solutions for greener software.
{"title":"Green Architectural Tactics for the Cloud","authors":"Giuseppe Procaccianti, P. Lago, G. Lewis","doi":"10.1109/WICSA.2014.30","DOIUrl":"https://doi.org/10.1109/WICSA.2014.30","url":null,"abstract":"Energy efficiency is a primary concern for the ICT sector. In particular, the widespread adoption of cloud computing technologies has drawn attention to the massive energy consumption of data centers. Although hardware constantly improves with respect to energy efficiency, this should also be a main concern for software. In previous work we analyzed the literature and elicited a set of techniques for addressing energy efficiency in cloud-based software architectures. In this work we codified these techniques in the form of Green Architectural Tactics. These tactics will help architects extend their design reasoning towards energy efficiency and to apply reusable solutions for greener software.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132052983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
State-of-the-art optimistic model versioning systems, which are critical to enable efficient team-based development of architectural models, are able to detect and help resolve basic conflicts arising during the merging of model versions. However, it is often overlooked that model merging may also cause severe syntactical and semantic inconsistencies. In this paper, we propose an approach to guide the resolution of inconsistencies detected in a merged architectural model. Our approach automatically finds and presents to the software architects all solutions for resolving all inconsistencies arisen during the merging of model versions. For inconsistencies that pre-exist in the model, our approach is able to suggest exactly which model elements should be changed to resolve them. Our approach is built upon a repair generation which can quickly derive resolutions for an inconsistency by examining its static and dynamic structure and forming concrete repair actions from changes in the versions to be merged. An empirical validation on a range of industrial models has demonstrated that our approach is scalable to both large models and large differences between model versions.
{"title":"Inconsistency Resolution in Merging Versions of Architectural Models","authors":"K. Dam, Alexander Reder, Alexander Egyed","doi":"10.1109/WICSA.2014.31","DOIUrl":"https://doi.org/10.1109/WICSA.2014.31","url":null,"abstract":"State-of-the-art optimistic model versioning systems, which are critical to enable efficient team-based development of architectural models, are able to detect and help resolve basic conflicts arising during the merging of model versions. However, it is often overlooked that model merging may also cause severe syntactical and semantic inconsistencies. In this paper, we propose an approach to guide the resolution of inconsistencies detected in a merged architectural model. Our approach automatically finds and presents to the software architects all solutions for resolving all inconsistencies arisen during the merging of model versions. For inconsistencies that pre-exist in the model, our approach is able to suggest exactly which model elements should be changed to resolve them. Our approach is built upon a repair generation which can quickly derive resolutions for an inconsistency by examining its static and dynamic structure and forming concrete repair actions from changes in the versions to be merged. An empirical validation on a range of industrial models has demonstrated that our approach is scalable to both large models and large differences between model versions.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121163909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
When architecting software systems, architects (with the contribution of other stakeholders) make several design decisions. These decisions could be related to the selection of the right components and connectors, the architectural style to be used, the distribution of various components, the deployment of software components into hardware devices, etc. Many methods have been proposed by the research community to help documenting several aspects of architectural design decisions including design alternatives, stakeholder concerns, decisions and the rationale for making such decisions and enhancing the decision-making process. Still, very little has been done to truly understand how architectural design decisions are made by group of practitioners, what information is documented, the tools used for helping documenting and how conflicts are managed. This study, by looking at principles and techniques for group decision making coming from other disciplines, aims to understand: a) how practitioners make group decisions in architecting software systems, b) how practiced group decision-making techniques relate to state-of-the-art techniques, and c) challenges companies face when making architecture-related group decisions. The study is conducted by using a questionnaire distributed to practitioners and researchers involved in group design decisions in industry. The results are used to drive some recommendations to improve the current group design decision process.
{"title":"A Study on Group Decision-Making in Software Architecture","authors":"Smrithi Rekha, H. Muccini","doi":"10.1109/WICSA.2014.15","DOIUrl":"https://doi.org/10.1109/WICSA.2014.15","url":null,"abstract":"When architecting software systems, architects (with the contribution of other stakeholders) make several design decisions. These decisions could be related to the selection of the right components and connectors, the architectural style to be used, the distribution of various components, the deployment of software components into hardware devices, etc. Many methods have been proposed by the research community to help documenting several aspects of architectural design decisions including design alternatives, stakeholder concerns, decisions and the rationale for making such decisions and enhancing the decision-making process. Still, very little has been done to truly understand how architectural design decisions are made by group of practitioners, what information is documented, the tools used for helping documenting and how conflicts are managed. This study, by looking at principles and techniques for group decision making coming from other disciplines, aims to understand: a) how practitioners make group decisions in architecting software systems, b) how practiced group decision-making techniques relate to state-of-the-art techniques, and c) challenges companies face when making architecture-related group decisions. The study is conducted by using a questionnaire distributed to practitioners and researchers involved in group design decisions in industry. The results are used to drive some recommendations to improve the current group design decision process.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127935005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Applying architecture knowledge promotes quality, reduces risks, and is crucial to best meet stakeholders' expectations. Current architecture knowledge is vast and ever-growing, however, it is also heterogeneous, diverse, disperse, and expressed at different levels of abstraction and rigor. In practice, architecture design is bounded by the architect's skills, experience, and the subset of knowledge he masters, and it also requires a huge effort to adjust such knowledge to the development scenario. The resulting architecture is therefore not as good as it could be. Moreover, the architect's effort is not repeatable as it is implicitly embedded in the architecture descriptions. Although model-based approaches are being used to capture particular domains and methods, most approaches lack either generality or homogeneity, making it hard to integrate, adapt and apply such knowledge. In this work, we use megamodeling to provide an homogeneous means for capturing architecture knowledge, making it shareable and reusable. We formally define a mapping from key architecture concepts to modeling artifacts. Also, an architecture design scripting language is used to capture the fine-grained design actions, making architecture design repeatable.
{"title":"Model-Based Formalization of Software Architecture Knowledge","authors":"Daniel Perovich, M. Bastarrica","doi":"10.1109/WICSA.2014.34","DOIUrl":"https://doi.org/10.1109/WICSA.2014.34","url":null,"abstract":"Applying architecture knowledge promotes quality, reduces risks, and is crucial to best meet stakeholders' expectations. Current architecture knowledge is vast and ever-growing, however, it is also heterogeneous, diverse, disperse, and expressed at different levels of abstraction and rigor. In practice, architecture design is bounded by the architect's skills, experience, and the subset of knowledge he masters, and it also requires a huge effort to adjust such knowledge to the development scenario. The resulting architecture is therefore not as good as it could be. Moreover, the architect's effort is not repeatable as it is implicitly embedded in the architecture descriptions. Although model-based approaches are being used to capture particular domains and methods, most approaches lack either generality or homogeneity, making it hard to integrate, adapt and apply such knowledge. In this work, we use megamodeling to provide an homogeneous means for capturing architecture knowledge, making it shareable and reusable. We formally define a mapping from key architecture concepts to modeling artifacts. Also, an architecture design scripting language is used to capture the fine-grained design actions, making architecture design repeatable.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124031885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Architecture evaluation has become a mature sub-discipline in architecting with high-quality practical and scientific literature available. However, publications on industrial applications and concrete experiences are rare. We want to fill this gap and share our experiences - having performed more than 50 architecture evaluations for industrial customers in the last decade. We compiled facts and consolidated our findings about architecture evaluations in industry. In this paper, we provide a critical retrospective on more than 50 projects and share our lessons learned. This industrial and practical perspective allows practitioners to benefit from our experience in their daily architecture work and scientific community to focus their research work on the generalizability of our findings.
{"title":"Software Architecture Evaluation in Practice: Retrospective on More Than 50 Architecture Evaluations in Industry","authors":"J. Knodel, Matthias Naab","doi":"10.1109/WICSA.2014.37","DOIUrl":"https://doi.org/10.1109/WICSA.2014.37","url":null,"abstract":"Architecture evaluation has become a mature sub-discipline in architecting with high-quality practical and scientific literature available. However, publications on industrial applications and concrete experiences are rare. We want to fill this gap and share our experiences - having performed more than 50 architecture evaluations for industrial customers in the last decade. We compiled facts and consolidated our findings about architecture evaluations in industry. In this paper, we provide a critical retrospective on more than 50 projects and share our lessons learned. This industrial and practical perspective allows practitioners to benefit from our experience in their daily architecture work and scientific community to focus their research work on the generalizability of our findings.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126540825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Every software program that interacts with a user requires a user interface. Model-View-Controller (MVC) is a common design pattern to integrate a user interface with the application domain logic. MVC separates the representation of the application domain (Model) from the display of the application's state (View) and user interaction control (Controller). However, studying the literature reveals that a variety of other related patterns exists, which we denote with Model-View- (MV) design patterns. This paper discusses existing MV patterns classified in three main families: Model-View-Controller (MVC), Model-View-View Model (MVVM), and Model-View-Presenter (MVP). We take a practitioners' point of view and emphasize the essentials of each family as well as the differences. The study shows that the selection of patterns should take into account the use cases and quality requirements at hand, and chosen technology. We illustrate the selection of a pattern with an example of our practice. The study results aim to bring more clarity in the variety of MV design patterns and help practitioners to make better grounded decisions when selecting patterns.
{"title":"A Journey through the Land of Model-View-Design Patterns","authors":"Artem Syromiatnikov, Danny Weyns","doi":"10.1109/WICSA.2014.13","DOIUrl":"https://doi.org/10.1109/WICSA.2014.13","url":null,"abstract":"Every software program that interacts with a user requires a user interface. Model-View-Controller (MVC) is a common design pattern to integrate a user interface with the application domain logic. MVC separates the representation of the application domain (Model) from the display of the application's state (View) and user interaction control (Controller). However, studying the literature reveals that a variety of other related patterns exists, which we denote with Model-View- (MV) design patterns. This paper discusses existing MV patterns classified in three main families: Model-View-Controller (MVC), Model-View-View Model (MVVM), and Model-View-Presenter (MVP). We take a practitioners' point of view and emphasize the essentials of each family as well as the differences. The study shows that the selection of patterns should take into account the use cases and quality requirements at hand, and chosen technology. We illustrate the selection of a pattern with an example of our practice. The study results aim to bring more clarity in the variety of MV design patterns and help practitioners to make better grounded decisions when selecting patterns.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123981750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper is an experience report of a long running Scrum project, conducted in a collaboration between industry and research, in a so called "Joint Research and Development Laboratory". Over time in the collaboration, we experienced a constant decrease in the pace of our development progress. Planning forward only within the limits of single sprints was the main reason for this. It resulted in a degenerating design and therefore a lack of flexibility that affected the agility of our project. Therefore, we introduced the concept of "epic-architectures", an architecture design for a coherent group of user stories. Shifting the planning horizon further, across single sprints, helped us to create more stable and reusable concepts and to construct simpler, more elegant, and more maintainable solutions. We were able to significantly reduce the refactoring effort and increase the development speed, without significant overhead. With reporting on our experiences we hope to provide practically applicable guidance on how to integrate lightweight architecting in agile development processes, to sustain agility while creating high quality products.
{"title":"Sustaining Agility through Architecture: Experiences from a Joint Research and Development Laboratory","authors":"Balthasar Weitzel, Dominik Rost, Mathias Scheffe","doi":"10.1109/WICSA.2014.38","DOIUrl":"https://doi.org/10.1109/WICSA.2014.38","url":null,"abstract":"This paper is an experience report of a long running Scrum project, conducted in a collaboration between industry and research, in a so called \"Joint Research and Development Laboratory\". Over time in the collaboration, we experienced a constant decrease in the pace of our development progress. Planning forward only within the limits of single sprints was the main reason for this. It resulted in a degenerating design and therefore a lack of flexibility that affected the agility of our project. Therefore, we introduced the concept of \"epic-architectures\", an architecture design for a coherent group of user stories. Shifting the planning horizon further, across single sprints, helped us to create more stable and reusable concepts and to construct simpler, more elegant, and more maintainable solutions. We were able to significantly reduce the refactoring effort and increase the development speed, without significant overhead. With reporting on our experiences we hope to provide practically applicable guidance on how to integrate lightweight architecting in agile development processes, to sustain agility while creating high quality products.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116915704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Requirements evolve over the development lifecycle of a software project. Agile practices are designed specifically to address this challenge while showing early and continuous progress towards project goals. Applying an agile approach allows stakeholders to adapt the scope and capabilities of a development release to changing market needs. More recently, an agile approach has been recommended for developing the architecture of software systems, enabling the design to support current requirements and early releases while evolving to meet future expectations. Our experience defining emergent software systems to build a product line architecture for advanced data analytics demonstrates the benefits that can be gained from prioritizing work activities and delaying architecture decisions. This paper proposes a process and ontology for agile architecture development. Only the necessary aspects for each evolutionary release are designed and prototyped, as determined by expectations of the identified application domain scenarios. Feedback from implementing the scenarios using the architecture extends our understanding of the requirements and provides the backlog for successive design iterations.
{"title":"Agile Software Architecture in Advanced Data Analytics","authors":"K. Eric Harper, A. Dagnino","doi":"10.1109/WICSA.2014.16","DOIUrl":"https://doi.org/10.1109/WICSA.2014.16","url":null,"abstract":"Requirements evolve over the development lifecycle of a software project. Agile practices are designed specifically to address this challenge while showing early and continuous progress towards project goals. Applying an agile approach allows stakeholders to adapt the scope and capabilities of a development release to changing market needs. More recently, an agile approach has been recommended for developing the architecture of software systems, enabling the design to support current requirements and early releases while evolving to meet future expectations. Our experience defining emergent software systems to build a product line architecture for advanced data analytics demonstrates the benefits that can be gained from prioritizing work activities and delaying architecture decisions. This paper proposes a process and ontology for agile architecture development. Only the necessary aspects for each evolutionary release are designed and prototyped, as determined by expectations of the identified application domain scenarios. Feedback from implementing the scenarios using the architecture extends our understanding of the requirements and provides the backlog for successive design iterations.","PeriodicalId":346971,"journal":{"name":"2014 IEEE/IFIP Conference on Software Architecture","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115200995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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