Examples of org.antlr.runtime.TokenRewriteStream

org.antlr.runtime.TokenRewriteStream
Useful for dumping out the input stream after doing some augmentation or other manipulations. You can insert stuff, replace, and delete chunks. Note that the operations are done lazily--only if you convert the buffer to a String. This is very efficient because you are not moving data around all the time. As the buffer of tokens is converted to strings, the toString() method(s) check to see if there is an operation at the current index. If so, the operation is done and then normal String rendering continues on the buffer. This is like having multiple Turing machine instruction streams (programs) operating on a single input tape. :) Since the operations are done lazily at toString-time, operations do not screw up the token index values. That is, an insert operation at token index i does not change the index values for tokens i+1..n-1. Because operations never actually alter the buffer, you may always get the original token stream back without undoing anything. Since the instructions are queued up, you can easily simulate transactions and roll back any changes if there is an error just by removing instructions. For example, CharStream input = new ANTLRFileStream("input"); TLexer lex = new TLexer(input); TokenRewriteStream tokens = new TokenRewriteStream(lex); T parser = new T(tokens); parser.startRule(); Then in the rules, you can execute Token t,u; ... input.insertAfter(t, "text to put after t");} input.insertAfter(u, "text after u");} System.out.println(tokens.toString()); Actually, you have to cast the 'input' to a TokenRewriteStream. :( You can also have multiple "instruction streams" and get multiple rewrites from a single pass over the input. Just name the instruction streams and use that name again when printing the buffer. This could be useful for generating a C file and also its header file--all from the same buffer: tokens.insertAfter("pass1", t, "text to put after t");} tokens.insertAfter("pass2", u, "text after u");} System.out.println(tokens.toString("pass1")); System.out.println(tokens.toString("pass2")); If you don't use named rewrite streams, a "default" stream is used as the first example shows.

      "A : 'a';\n" +
      "B : 'b';\n" +
      "C : 'c';\n");
    CharStream input = new ANTLRStringStream("abcccba");
    Interpreter lexEngine = new Interpreter(g, input);
    TokenRewriteStream tokens = new TokenRewriteStream(lexEngine);
    tokens.fill();
    tokens.replace(2, 4, "xyz");
    String result = tokens.toString(0,6);
    String expecting = "abxyzba";
    assertEquals(expecting, result);
  }

View Full Code Here

      "A : 'a';\n" +
      "B : 'b';\n" +
      "C : 'c';\n");
    CharStream input = new ANTLRStringStream("abcccba");
    Interpreter lexEngine = new Interpreter(g, input);
    TokenRewriteStream tokens = new TokenRewriteStream(lexEngine);
    tokens.fill();
    tokens.replace(2, 4, "xyz");
    tokens.replace(3, 5, "foo"); // overlaps, error
    Exception exc = null;
    try {
      tokens.toString();
    }
    catch (IllegalArgumentException iae) {
      exc = iae;
    }
    String expecting = "replace op boundaries of <ReplaceOp@[@3,3:3='c',<6>,1:3]..[@5,5:5='b',<5>,1:5]:\"foo\"> overlap with previous <ReplaceOp@[@2,2:2='c',<6>,1:2]..[@4,4:4='c',<6>,1:4]:\"xyz\">";

View Full Code Here

        // PARSE INPUT AND BUILD AST
        ANTLRInputStream input = new ANTLRInputStream(System.in);
        CMinusLexer lexer = new CMinusLexer(input);       // create lexer
        // create a buffer of tokens pulled from the lexer
        // Must use TokenRewriteStream not CommonTokenStream!
        TokenRewriteStream tokens = new TokenRewriteStream(lexer);
        CMinusParser parser = new CMinusParser(tokens);   // create parser
        CMinusParser.program_return r = parser.program(); // parse program






        // WALK TREE AND REWRITE TOKEN BUFFER
        // get the tree from the return structure for rule prog
        CommonTree t = (CommonTree)r.getTree();
        // create a stream of tree nodes from AST built by parser
        CommonTreeNodeStream nodes = new CommonTreeNodeStream(t);
        // tell it where it can find the token objects
        nodes.setTokenStream(tokens);
        Gen gen = new Gen(nodes);
        gen.program(); // invoke rule program
        System.out.println(tokens.toString()); // emit tweaked token buffer


    }

View Full Code Here

   */
  public ASTNode parse(String command, Context ctx) throws ParseException {
    LOG.info("Parsing command: " + command);


    HiveLexerX lexer = new HiveLexerX(new ANTLRNoCaseStringStream(command));
    TokenRewriteStream tokens = new TokenRewriteStream(lexer);
    if (ctx != null) {
      ctx.setTokenRewriteStream(tokens);
    }
    HiveParserX parser = new HiveParserX(tokens);
    parser.setTreeAdaptor(adaptor);

View Full Code Here

   */
  public ASTNode parse(String command, Context ctx) throws ParseException {
    LOG.info("Parsing command: " + command);


    HiveLexerX lexer = new HiveLexerX(new ANTLRNoCaseStringStream(command));
    TokenRewriteStream tokens = new TokenRewriteStream(lexer);
    if (ctx != null) {
      ctx.setTokenRewriteStream(tokens);
    }
    HiveParserX parser = new HiveParserX(tokens);
    parser.setTreeAdaptor(adaptor);

View Full Code Here

   */
  public ASTNode parse(String command, Context ctx) throws ParseException {
    LOG.info("Parsing command: " + command);


    HiveLexerX lexer = new HiveLexerX(new ANTLRNoCaseStringStream(command));
    TokenRewriteStream tokens = new TokenRewriteStream(lexer);
    if (ctx != null) {
      ctx.setTokenRewriteStream(tokens);
    }
    HiveParserX parser = new HiveParserX(tokens);
    parser.setTreeAdaptor(adaptor);

View Full Code Here

      "A : 'a';\n" +
      "B : 'b';\n" +
      "C : 'c';\n");
    CharStream input = new ANTLRStringStream("abc");
    Interpreter lexEngine = new Interpreter(g, input);
    TokenRewriteStream tokens = new TokenRewriteStream(lexEngine);
    tokens.LT(1); // fill buffer
    tokens.insertBefore(0, "0");
    String result = tokens.toString();
    String expecting = "0abc";
    assertEquals(expecting, result);
  }

View Full Code Here

      "A : 'a';\n" +
      "B : 'b';\n" +
      "C : 'c';\n");
    CharStream input = new ANTLRStringStream("abc");
    Interpreter lexEngine = new Interpreter(g, input);
    TokenRewriteStream tokens = new TokenRewriteStream(lexEngine);
    tokens.LT(1); // fill buffer
    tokens.insertAfter(2, "x");
    String result = tokens.toString();
    String expecting = "abcx";
    assertEquals(expecting, result);
  }

View Full Code Here

      "A : 'a';\n" +
      "B : 'b';\n" +
      "C : 'c';\n");
    CharStream input = new ANTLRStringStream("abc");
    Interpreter lexEngine = new Interpreter(g, input);
    TokenRewriteStream tokens = new TokenRewriteStream(lexEngine);
    tokens.LT(1); // fill buffer
    tokens.insertBefore(1, "x");
    tokens.insertAfter(1, "x");
    String result = tokens.toString();
    String expecting = "axbxc";
    assertEquals(expecting, result);
  }

View Full Code Here

      "A : 'a';\n" +
      "B : 'b';\n" +
      "C : 'c';\n");
    CharStream input = new ANTLRStringStream("abc");
    Interpreter lexEngine = new Interpreter(g, input);
    TokenRewriteStream tokens = new TokenRewriteStream(lexEngine);
    tokens.LT(1); // fill buffer
    tokens.replace(0, "x");
    String result = tokens.toString();
    String expecting = "xbc";
    assertEquals(expecting, result);
  }

View Full Code Here

0 1 2 3 4 5 6 7 8 9

TOP

Related Classes of org.antlr.runtime.TokenRewriteStream

com.google.jstestdriver.coverage.CodeInstrumentor

com.narirelays.ems.utils.Interpreters.CMinus.TestRewrite

com.olabini.jescov.CodeInstrumentor

com.redhat.ceylon.tools.version.CeylonVersionTool

org.antlr.test.TestTokenRewriteStream

org.apache.hadoop.hive.ql.exec.ExplainSQRewriteTask

org.apache.hadoop.hive.ql.parse.ParseDriver

org.docx4j.model.datastorage.XPathEnhancerParser

org.orangegears.parser.ExpressionTree

All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.