Wiktionary bytecode Refimprove date January 2009 Bytecode , also known as p code machine p code portable .... The name bytecode stems from instruction sets which have one byte opcode s followed by optional parameters. Intermediate representations such as bytecode may be output by programming language ... and operating system dependence by allowing the same code to run on different platforms. Bytecode .... Execution A bytecode program may be executed by parsing and directly executing the instructions, one at a time. This kind of bytecode interpreter is very portable. Some systems, called dynamic translators, or just in time compilation just in time JIT compilers, translate bytecode into machine language ..., but doesn t lose the portability of the bytecode itself. For example, Java programming language ... to translate the bytecode to machine code before execution. This introduces a delay before a program is run, when bytecode is compiled to native machine code, but improves execution speed considerably ... execute a program in two phases, first compiling the source code into bytecode, and then passing the bytecode to the virtual machine. Therefore, there are virtual machines for Java programming language ... of Flash Player and AIR. ActionScript code is typically transformed into bytecode format by a compiler ... programming language BANCStar , originally bytecode for an interface building tool but used as a language in its own right. Byte Code Engineering Library Java Virtual Machine C to bytecode compilers C to Java Virtual Machine compilers CLISP implementation of Common Lisp compiles only to bytecode CMUCL and Scieneer Common Lisp implementations of Common Lisp can compile either to bytecode or to native code bytecode is much more compact Dalvik bytecode, designed for the Android operating system ... into bytecode. This architecture allows users to customize the editor with a high level language, which after compilation into bytecode yields reasonable performance. Embeddable Common Lisp ... more details
Java bytecode is the form of instructions that the Java virtual machine executes. Each bytecode opcode ... programming language Java programmer does not need to be aware of or understand Java bytecode at all. However, as suggested in the IBM developerWorks journal, Understanding bytecode and what bytecode ... developerworks ibm library it haggar bytecode Understanding bytecode makes you a better programmer ref Instructions See also Java bytecode instruction listings As each byte has 256 potential ... must be used . Model of computation The model of computation of Java bytecode is that of a stack ... values and move the result to a different location. Similar disassembled bytecode might look like ... Java bytecode is Java. Originally only one compiler existed, the javac compiler from Sun Microsystems, which compiles Java source code to Java bytecode but because all the specifications for Java bytecode are now available, other parties have supplied compilers that produce Java bytecode. Examples of other compilers include Jikes , compiles from Java to Java bytecode developed by IBM , implemented in C Espresso, compiles from Java to Java bytecode Java 1.0 only GCJ , the GNU Compiler for Java, compiles from Java to Java bytecode it is also able to compile to native machine code and is available ... assemblers to enable writing Java bytecode by hand. Assembly code may be also generated by machine, for example ... definition. Method bodies are specified using bytecode instructions. ref http www.judoscript.org ... programming language to Java bytecode Java Virtual Machine C to bytecode compilers C to Java byte code compiler s Clojure MIDletPascal JavaFX Script code is also compiled to Java bytecode. Execution Java bytecode is designed to be executed in a Java virtual machine . There are several virtual ... Java bytecode in a Java virtual machine is not desirable, a developer can also compile Java source code or Java bytecode directly to native machine code with tools such as the GCJ GNU Compiler for Java ... more details
Main Java bytecode This is a list of the instructions that make up the Java bytecode , an abstract machine language that is ultimately executed by the Java virtual machine . The Java bytecode is generated by language compilers targeting the Java Platform , most notably the Java programming language . class wikitable sortable scope col Mnemonic scope col Opcode br in hex scope col Other bytes scope col Stack br before after scope col class unsortable Description aaload align center 32 arrayref, index value load onto the stack a reference from an array aastore align center 53 arrayref, index, value store into a reference in an array aconst null align center 01 null push a null reference onto the stack aload align center 19 1 index objectref load a reference onto the stack from a local variable index aload 0 align center 2a objectref load a reference onto the stack from local variable 0 aload 1 align center 2b objectref load a reference onto the stack from local variable 1 aload 2 align center 2c objectref load a reference onto the stack from local variable 2 aload 3 align center 2d objectref load a reference onto the stack from local variable 3 anewarray align center bd 2 indexbyte1, indexbyte2 count arrayref create a new array of references of length count and component type identified by the class reference index indexbyte1 < < 8 indexbyte2 in the constant pool areturn align center b0 objectref empty return a reference from a method arraylength align center be arrayref length get the length of an array astore align center 3a 1 index objectref store a reference into a local variable index astore 0 align center 4b objectref store a reference into local variable 0 astore ... for future use See also Java bytecode , a general description of the java bytecode within the context of the JVM ARM9E , a Central processing unit CPU family with direct Java bytecode execution ability Common Intermediate Language CIL , a similar bytecode specification that runs on the Common ... more details
.abc may be a file extension for ActionScript bytecode Clean programming language bytecode abc notation , a language for notating music using the ASCII character set See also ABC disambiguation disambig ... more details
Infobox Software name Javassist logo screenshot caption developer Shigeru Chiba programmer Shigeru Chiba latest release version 3.15.0.GA latest release date release date 2011 07 08 latest preview version latest preview date operating system Cross platform programming language Java programming language Java genre bytecode Engineering Library license dual license of the Mozilla Public License MPL and LGPL . website http www.csg.is.titech.ac.jp chiba javassist Javassist Java programming assist ant is a Java programming language Java software library library providing a means to manipulate the Java bytecode of an application. ref cite web title Javassist url http www.jboss.org javassist publisher JBoss Community ref In this sense Javassist provides the support for structural reflection programming reflection , i.e. the ability to change the implementation of a class programming class at Run time program lifecycle phase run time . Bytecode manipulation is performed at Loader computing load time through a provided class loader . Javassist Java Programming Assistant makes Java bytecode manipulation simple. It is a class library for editing bytecodes in Java it enables Java programs to define a new class at runtime and to modify a class file when the JVM loads it. Unlike other similar bytecode editors, Javassist provides two levels of API source level and bytecode level. If the users use the source level API, they can edit a class file without knowledge of the specifications of the Java bytecode. The whole API is designed with only the vocabulary of the Java language. You can even specify inserted bytecode in the form of source text Javassist compiles it on the fly. On the other hand, the bytecode level API allows the users to directly edit a class file as other editors. Uses Javassist can be used for the following For specifying the bytecode using source code can compile a fragment of source text online e.g., just a single statement For Aspect Oriented Programming AOP can ... more details
code analysis FindBugs uses BCEL to analyze Java bytecode for code idioms which indicate bugs ... index.html Jakarta ByteCode Engineering Library The BCEL Project Home Page. http jakarta.apache.org ... more details
JPF may refer to one of the following Just Plain Folks Music Organization Japonica Polonica Fantastica Java Pathfinder , a system to verify executable Java bytecode programs Jeunesse Populaire Fran aise , a French youth fascist organization of 1940s JPEG 2000 , a digital image format file extension .jpf disambig ja JPF ... more details
. http www.drgarbage.com bytecode visualizer lt.html Bytecode Visualizer LT free Eclipse plugin for viewing and debugging Java bytecode which makes use of ASM library Category OW2 Consortium Category ... more details
The string pyc can refer to as an abbreviation PYC Potsdam er Yacht Club pyc a compiler for Python programming language Python bytecode , compiling .py code into .pyc code PYC Shatin Pui Ying College in Hong Kong, China PyC Pyrolytic carbon as a prefix PYc Coastal Patrol Yacht Patrol Yacht coastal United States Navy see List of patrol vessels of the United States Navy as a stock ticker PYC Primary Corp. disambig ... more details
Visual Eiffel is an implementation of the Eiffel programming language Eiffel programming language developed and distributed by Object Tools GmbH, a German company. Visual Eiffel provides an integrated development environment running on Microsoft Windows . A major design goal is to provide an environment that, unlike EiffelStudio , does not use an original user interface paradigm but instead is comfortable to programmers familiar with such tools as Microsoft s Visual Studio and Borland s Borland Delphi Delphi . Visual Eiffel includes a Display Machine for developing GUI applications. While many other Eiffel compilers generate C programming language C , Java programming language Java bytecode or bytecode for .NET framework .NET , the Visual Eiffel compiler generates native X86 code. The compiler not the graphical environment is, besides Windows, also available on Linux . Licencing is free for personal use with banner or commercial, with the core GPL. http visual eiffel.com Visual Eiffel web site Category Integrated development environments compu prog stub ... more details
A Java processor is the implementation of the Java Virtual Machine JVM in hardware. In other words the Java bytecode bytecodes that make up the instruction set of the abstract machine become the instruction set of a concrete machine. Implementations Up to now only a few Java processors are available picoJava was the first attempt by Sun Microsystems to build a Java processor http www.ajile.com index.php?option com content&view article&id 2&Itemid 6 aJ102 and http www.ajile.com index.php?option com content&view article&id 3&Itemid 7 aJ200 from http www.ajile.com aJile Systems, Inc. . Available on boards from http jstamp.systronix.com Systronix http www.imsystech.com Cjip from Imsys Technologies. Available on boards and with wireless radios from http www.avidwireless.com site AVIDdirector.htm AVIDwireless ref Imsys hedges bets on Java microcode Writable control stores rewritable microcode chip has instruction sets for Java, Forth, C C by Tom R. Halfhill http www.imsystech.com press room press archive press micro p report.pdf ref http ipr.ira.uka.de komodo komodoEng.html Komodo is a multithreaded Java microcontroller for research on real time scheduling http www.inf.ufrgs.br en FemtoJava is a research project to build an application specific Java processor ARM9E ARM926EJ S is an ARM processor able to run Java bytecode, this technology being named Jazelle Java Optimized Processor ref cite doi 10.1016 j.sysarc.2007.06.001 ref for FPGA s. A PhD thesis is http www.jopdesign.com thesis index.jsp available http shap.inf.tu dresden.de SHAP bytecode processor from the TU Dresden http www.ee.cityu.edu.hk hisc architecture.html jHISC ref cite doi 10.1016 j.micpro.2005.12.007 ref provides hardware support for object oriented functions http www.vivaja.com ObjectCore is a multicore Java processor designed by http www.vivaja.com Vivaja Technologies . http www.templecomputing.com Java Offload Engine JOE is a high performance Java co processor from http www.templecomputing.com Temple ... more details
security guarantees. JIT builds upon two earlier ideas in run time environments bytecode compilation ... to executing it natively, for example bytecode into native machine code . Several modern runtime environments ... Java , rely on JIT compilation for high speed code execution. Overview In a bytecode compiled system, source code is translated to an intermediate representation known as bytecode . Bytecode is not the machine code for any particular computer, and may be portable among computer architectures. The bytecode ..., a traditional interpreted virtual machine will simply interpret the bytecode, generally with much ... to bytecode, with even worse performance. Statically compiled code or native code is compiled prior ..., while maintaining the advantages of bytecode interpretation Much of the heavy lifting of parsing ... to deployment compilation from bytecode to machine code is much faster than compiling from source. The deployed bytecode is portable, unlike native code. Since the runtime has control over the compilation, like interpreted bytecode, it can run in a secure sandbox. Compilers from bytecode to machine code are easier to write, because the portable bytecode compiler has already done much of the work ... of speed. Although this is possible with statically compiled garbage collected languages, a bytecode ... taken to load and compile the bytecode. Sometimes this delay is called startup time delay . In general ... monitors which sequences of bytecode are frequently executed and translates them to machine code for direct execution on the hardware. For bytecode which is executed only a few times, this saves the compilation time and reduces the initial latency for frequently executed bytecode, JIT compilation ... of the number of times a method has executed combined with the bytecode size of a method as a heuristic ... .aspx ref Ngen pre compiles or pre jits bytecode in a Common Intermediate Language image into machine ... project Dynamo was an experimental JIT compiler where the bytecode format and the machine code format ... more details
midp articles deploy ref MIDlet security Bytecode verification Due to the memory and processing power ..., incomplete class verification. The bytecode for the MIDlet classes must therefore be Java Virtual Machine Bytecode verifier pre verified by using a preverifier to annotate the class files to enable ... the annotations are using attributes of the bytecode to make the notes for the Mobile VM to read ... more details
A Java compiler is a compiler for the Java programming language Java programming language . The most common form of output from a Java compiler is Class file format Java class files containing platform neutral Java bytecode . There exist also compilers emitting optimized Machine code native machine code for a particular hardware operating system combination. Most Java to bytecode compilers, Jikes being a well known exception, do virtually no Optimization computer science optimization , leaving this until Run time program lifecycle phase run time to be done by the JRE Citation needed date April 2007 . The Java Virtual Machine JVM loads the class files and either interpreter computing interprets the bytecode or just in time compilation just in time compiles it to machine code and then possibly optimizes it using dynamic compilation . The very first Java compiler developed by Sun Microsystems was written in C using some libraries from C . Citation needed date February 2007 Major Java compilers As of 2010, the following are major Java compiler s citation needed date February 2012 javac , included in Java Development Kit JDK from Sun Microsystems , open sourced since 13 November 2006. GNU Compiler for Java , a part of the GNU Compiler Collection , which compiles C programming language C , Fortran , Pascal programming language Pascal and other programming language s besides Java. It can also generate native code using the back end of GCC. ECJ, the Eclipse Compiler for Java, is an open source incremental compiler used by the Eclipse software Eclipse project. Java decompilers A Java decompiler tries to reverse the process of compiling, that is it tries to decompile Java bytecode files .class back to Java source files .java . DJ Java Decompiler http www.neshkov.com Uses JAD 10 use trial version JAD JAva Decompiler JAD , written in C , free for non commercial use. JD Java Decompiler JD http java.decompiler.free.fr , younger project, includes GUI, optional Eclipse plugin. http ... more details
lowercase title eAccelerator Not to be confused with the computer security company eAcceleration . eAccelerator is a PHP accelerator fork software derived from the MMCache extension computing extension for the PHP programming language . eAccelerator provides a bytecode cache computing cache . eAccelerator is open source and thereby free to use and distribute. Old and unmaintained versions also provided an encoder. Every time a PHP script is accessed, PHP usually parses and compiles scripts to bytecode . Once installed, eAccelerator optimizes the compiled bytecode and caches this to shared memory or disk or both. Upon subsequent accesses to a script, eAccelerator will access cached bytecode if it is available instead of the script being compiled. This avoids the performance overhead of repeated parsing and compilation. Previous eAccelerator versions also provided functions ref http bart.eaccelerator.net doc phpdoc eAccelerator 0.9.5 PHP interface documentation Bot generated title ref for use in PHP scripts that allow access to shared memory , automatic web caching web content caching , and other related tasks. These were removed as of version 0.9.6rc1. Old eAccelerator versions had an encoder component that creates a file that cannot be as easily read as a normal PHP script, offering some code protection. A dedicated extension named eLoader is available to process such encoded scripts if the eAccelerator extension is not desired. This functionality has been removed from the current developer version and will not be part of the next release. References This article uses the Cite.php citation mechanism. If you would like more information on how to add references to this article, please see http meta.wikimedia.org wiki Cite Cite.php div class references small style moz column count 2 column count 2 references div See also Zend Performance Suite Alternative PHP Cache External links https eaccelerator.net eAccelerator Web Site http www.sitebuddy.com PHP Accelerators eAcce ... more details
Jazelle DBX Direct Bytecode eXecution allows some ARM architecture ARM processors to execute Java bytecode in hardware as a third execution state alongside the existing ARM and Thumb modes. ref http www.arm.com products multimedia java jazelle.html ref Jazelle functionality was specified in the ARMv5TEJ architecture ref name armarm and the first processor with Jazelle technology was the ARM926EJ S . ref http www.us.design reuse.com news news6919.html Shanghai Jade Licenses ARM Prime Starter Kit for DCP SoC ref Jazelle is denoted by a J appended to the CPU name, except for post v5 cores where it is required albeit only in trivial form for architecture conformance. Jazelle RCT Runtime Compilation Target is a different technology and is based on ThumbEE mode and supports ahead of time AOT and just in time JIT compilation with Java and other execution environments. The most prominent use of Jazelle ... used bytecode operations. ARM claims that approximately 95 of bytecode in typical program usage ... as Java bytecode . However, ARM have chosen to remain quiet on the exact execution environment ... a bytecode such as following a return from interrupt will re execute the complete sequence of related ... Environments ref A pointer to the next bytecode goes in r14, ref Intel, ftp download.intel.com ... is not generally user visible except during debugging. CPSR Mode indication Java bytecode is indicated ..., the system must know where to begin decoding. Because the current state is held in the CPSR, the bytecode ... Java bytecode is restarted. ref name accelerating Following an entry into the Jazelle state mode ... case will cause a branch to an ARM exception mode, as will a Java bytecode of 0xff, which is used ... an unhandled bytecode is encountered, or an exception occurs. Between 134 and 149 bytecodes out ... of next bytecode r13 r14 jpc next bytecode r15 pc current bytecode cpsr J bit current instruction ... Jazelle and Direct Bytecode Execution of JVM bytecodes. In implementation terms, only trivial ... more details
Mocha is a Java programming language Java decompiler , which allows programmers to translate a program s bytecode into source code . A beta version of Mocha was released in 1996, by Dutch developer Hanpeter van Vliet, alongside an obfuscator named Crema . A controversy erupted and he temporarily withdrew Mocha from public distribution. ref http news.com.com 2100 1023 222781.html Mocha pulled off the Net ref As of 2009 the program is still available for distribution, and may be used freely as long as it is not modified. Borland s JBuilder includes a decompiler based on Mocha. See also JAD JAva Decompiler References reflist External links http www.brouhaha.com eric software mocha Java Decompiler http www.javaworld.com javaworld javatips jw javatip22.html Protect your bytecodes from reverse engineering decompilation Category Java decompilers ... more details
The JStik is a microcontroller based on the aJile Systems line of embedded Java processor s. It is novel in that it uses Java programming language Java Java bytecode byte code as the native Machine code machine language . This makes it very fast at executing Java code while still maintaining the benefits of programming in a high level language like Java. External links http www.systronix.com jstik Jstik JStik Home http www.systronix.com Systronix Inc. Makers of the JStik system. http www.ajile.com aJile Systems Inc. Makers of the Silicon Category Microcontrollers microcompu stub ... more details
opcode. ActionScript Memory.writeInt 1, 0 Pseudo bytecode GetLex Memory PushByte 1 PushByte 0 CallVoid ... TAAS is an intermediate representation of ActionScript Bytecode in optional Static single assignment ... more details
. Source code is compiled to Java bytecode, which is verified, interpreted or JIT compiled for the native ... virtual machine JVM is a virtual machine that can execute Java bytecode . It is the code execution ... hardware and on standard operating system s. A JVM provides an environment in which Java bytecode can ... platform platforms . The use of the same bytecode for all JVMs on all platforms allows Java to be described ... software platform Java platform . Java bytecode is an intermediate language which is typically compiled ... language Ada source code can be compiled to Java bytecode and executed on a JVM. Oracle Corporation ... system Dynamic typing dynamically typed languages the existing Java bytecode JVM instruction set ... JVM coverage last Krill first Paul date 2008 01 31 accessdate 2008 02 06 ref Bytecode verifier ... , and the verifier. The JVM verifies all bytecode before it is executed. This verification consists ... only some bytecode sequences in valid programs, e.g. a branch computer science jump branch instruction ... s such as the Plessey 250 , and IBM System 38 . The original specification for the bytecode verifier ... bytecode language and verifier. In Proceedings of the 14th ACM SIGPLAN conference on Object oriented ... York, NY, USA, 147 166. DOI 10.1145 320384.320397 http doi.acm.org 10.1145 320384.320397 ref Bytecode instructions Main Java bytecode The JVM has instruction computer science instructions for the following ... the bytecode semantically the same way, but the actual implementation may be different. More complex than just emulating bytecode is compatibly and efficiently implementing the Java Class Library ..., clipboard software clipboard or network. C to bytecode compilers primary sources section date November ... set, Java bytecode , for which code can be generated. The JVM was originally designed ... in the form of a bytecode instruction set and a runtime system that is general enough that it can ... specification. That requires C programming language C to bytecode compilers to provide their own lax ... more details
of objects . Bytecode Java Card bytecode run by the Java Card Virtual Machine is a functional subset of Java Java 2 Standard Edition Java bytecodebytecode run by a Java Virtual Machine, but uses a different encoding optimized for size. A Java Card applet thus typically uses less bytecode than ... environment as well as the bytecode have therefore been adapted to manage persistent objects ... must be atomic. The individual write operations performed by individual bytecode instructions and API ... to develop and debug a Java Card program caveat even if debugging occurs with Java bytecode ... bytecode and test in a real Java Card smart card early on to get an idea of the performance further ... more details
. However, various systems of encryption and obfuscation exist. Delivery of intermediate code, such as bytecode .... Variations Bytecode interpreters Main Bytecode There is a spectrum of possibilities between .... For example, Emacs Lisp is compiled to bytecode , which is a highly compressed and optimized representation ... . This compiled code is then interpreted by a bytecode interpreter itself written in C programming ... not in hardware, but in the bytecode interpreter. The same approach is used with the Forth ... code a bytecode , which is then interpreted by a virtual machine . Control table s that do not necessarily ... via customized interpreters in similar fashion to bytecode interpreters. Abstract Syntax Tree interpreters ... to be parsed just once. As an advantage over bytecode, the AST keeps the global program structure and relations between statements which is lost in a bytecode representation , and when compressed ... been proposed as a better intermediate format for Just in time compilers than bytecode. Also, it allows ... than a bytecode interpreter, because of nodes related to syntax performing no useful work, of a less ... memory use when the bytecode or AST is first compiled. Adaptive optimization is a complementary ... more details
JBC may refer to TOC right Organizations Editora JBC Japan Brazil Communication , a Brazilian publisher Jamaica Broadcasting Corporation , a public broadcasting company JoongAng Broadcasting Corporation, the broadcast media arm of the JoongAng Ilbo JoongAng Media Network JBC, a Korean language radio station in Los Angeles, California, see KYPA Japan Boxing Commission Japan Bowling Congress , the major sanctioning body for bowling in Japan John Bosco College, former name of De La Salle John Bosco College in the Philippines Johnson Bible College , in Knoxville, Tennessee, USA Jamestown Business College , a for profit institution in Jamestown, New York Jelly Belly Kenda , UCI Code JBC, Jelly Belly Cycling Team, an elite men s cycling team Judicial and Bar Council Philippines , a body that makes recommendations to fill judicial vacancies Science, technology, and computers JBC Soldering S.L., a manufacturer of soldering tools for electronics Java programming language Java Bytecode http www.google.de search?q JBC Java, http www.google.de search?q Java Bytecode JBC Java programming language Java Beans Component http www.google.de search?q JBC Java, http www.abbreviations.com b1.aspx?KEY 381390 Of course a bit of information as general and small as that is NOT legally copyrightable by STANDS4 LLC, whatever their claims or whining. Java programming language Java Batch Creator http www.google.de search?q JBC Java, http www.antionline.com archive index.php t 256641.html JBoss Cache , a component of JBoss Middleware that caches frequently accessed Java objects to improve application performance Journal of Biological Chemistry , a publication of The American Society for Biochemistry and Molecular Biology Jinbei car , a car brand name of Brilliance Jinbei Automobile Co., Ltd. Other uses Jews by Choice , someone who converted to Judaism JBC group , a Lithuanian hip hop group Junior Bacon Cheeseburger , a Wendy s product Joint Battle Command Platform, or JBC P, see Project Manager ... more details
Adaptive optimization is a technique in computer science that performs dynamic recompilation of portions of a computer program program based on the current execution profile. With a simple implementation, an adaptive optimizer may simply make a trade off between Just in time compilation and interpreting instructions. At another level, adaptive optimization may take advantage of local data conditions to optimize away branches and to use inline expansion to decrease context switch ing. Consider a hypothetical banking application that handles transactions one after another. These transactions may be checks, deposits, and a large number of more obscure transactions. When the program executes, the actual data may consist of clearing tens of thousands of checks without processing a single deposit and without processing a single check with a fraudulent account number. An adaptive optimizer would compile assembly code to optimize for this common case. If the system then started processing tens of thousands of deposits instead, the adaptive optimizer would recompile the assembly code to optimize the new common case. This optimization may include inlining code or moving error processing code to secondary cache. Deoptimization In some systems, notably the Java Virtual Machine Citation needed date June 2011 , execution over a range of Java bytecode bytecode instructions can be provably reversed. This allows an adaptive optimizer to make risky assumptions about the code. In the above example, the optimizer may assume all transactions are checks and all account numbers are valid. When these assumptions prove incorrect, the adaptive optimizer can unwind to a valid state and then interpret the byte code instructions correctly. See also Java performance Adaptive optimization Adaptive optimization in Java External links http citeseer.ist.psu.edu arnold00adaptive.html CiteSeer for Adaptive Optimization in the Jalape o JVM 2000 by Matthew Arnold, Stephen Fink, David Grove, Michael Hind ... more details
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