antlr

I am trying mock sql syntax to build a simple sql like interface to a key-value storage. The values are essentially POJOs An example would be select A.B.C from OBJ_POOL where A.B.X = 45 AND A.B.Y > '88' AND A.B.Z != 'abc'; OBJ_POOL is just a list of POJOs of the same class. In this example A would be the base class. Class A Class B String C Integer X String Y String Z Now A.B.C is equivalent A.getB().getC() I am using Antlr to parse the above statement to get an AST, and then hoping to use Apache BeanUtils to reflectively get/set the field names. I wrote the grammar thats builds an AST Now I

is it possible to invoke a rule from a different grammar? the purpose is to have two languages in the same file, the second language starting by an (begin ...) where ... is in the second language. the grammar should invoke another grammar to parse that second language. for example: grammar A; start_rule : '(' 'begin' B.program ')' //or something like that ; grammar B; program : something* EOF ; something : ... ; Your question could be interpreted in (at least) two ways: separate rules from a large grammar into separate grammars; parse a separate language inside your "main" language (island

I'm looking for a good parser generator that I can use to read a custom text-file format in our large commercial app. Currently this particular file format is read with a handmade recursive parser but the format has grown and complexified to the point where that approach has become unmanageable. It seems like the ultimate solution would be to build a proper grammar for this format and then use a real parser generator like yacc to read it, but I'm having trouble deciding which such generator to use or even if they're worth the trouble at all. I've looked at ANTLR and Spirit, but our project has

在使用JPA的仓储repository进行查询时，经常用到findAllbyId的方法： repository.findAllbyId() 但如果像下面的代码，当list的size量太大的话，就会报栈溢出的的错误：java.lang.StackOverflowError @RequestMapping("/stackOverFlow") public Integer stackOverFlow() { List<String> ids = new ArrayList<>(); for (int i = 0; i < 5000; i++) { ids.add("123123123123"); } List<BillDO> allById = dwBillRepository.findAllById(ids); return allById.size(); } 报错信息如下： Caused by: java.lang.StackOverflowError at antlr.BaseAST.toString(BaseAST.java:333) ~[antlr-2.7.7.jar:?] at antlr.BaseAST.toStringList(BaseAST.java:341) ~[antlr-2.7.7.jar:?] at antlr.BaseAST.toStringList

I want to generate an antlr lexer at runtime -- that is, generate the grammar and from the grammar generate the lexer class, and its supporting bits at runtime. I am happy to feed it into the the java compiler, which is accessible at runtime. Here's a quick and dirty way to: generate a combined (!) ANTLR grammar .g file given a String as grammar-source, and create a Parser & Lexer from this .g file, compile the these Parser & Lexer .java files, create instances of the Parser & Lexer classes and invoke the entry point of the parser. Main.java import java.io.*; import javax.tools.*; import java

// Create a scanner that reads from the input stream passed to us CSLexer lexer = new CSLexer(new ANTLRFileStream(f)); tokens.TokenSource = lexer; // Create a parser that reads from the scanner CSParser parser = new CSParser(tokens); // start parsing at the compilationUnit rule CSParser.compilation_unit_return x = parser.compilation_unit(); object ast = x.Tree; What can I do with the x which is of compilation_unit_return type, to extract its root, its classes, its methods etc? Do I have to extract its Adaptor out? How do I do that? Note that the compilation_unit_return is defined as such in my

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I want to generate an antlr lexer at runtime -- that is, generate the grammar and from the grammar generate the lexer class, and its supporting bits at runtime. I am happy to feed it into the the java compiler, which is accessible at runtime. 回答1: Here's a quick and dirty way to: generate a combined (!) ANTLR grammar .g file given a String as grammar-source, and create a Parser & Lexer from this .g file, compile the these Parser & Lexer .java files, create instances of the Parser & Lexer classes and invoke the entry point of the parser. Main

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I have a simple HelloWorld.g4 grammar (see it at the bottom). I am able to successfully generate the .py files using this: set CLASSPATH=.;antlr-complete.jar;%CLASSPATH% java org.antlr.v4.Tool -Dlanguage=Python2 HelloWorld.g4 Now I would like to use the TestRig with the -gui flag to generate a parse tree GUI. I have the ANTRL Python runtime installed ( antlr4-python2-runtime-4.5.tar.gz ). I can open a Python interpreter and type: import antlr4 and the interpreter recognizes the antlr4 module. When I run the TestRig like this: set CLASSPATH=.