Java tutorial
/* * Copyright (c) 2012 Sam Harwell, Tunnel Vision Laboratories LLC * All rights reserved. * * The source code of this document is proprietary work, and is not licensed for * distribution. For information about licensing, contact Sam Harwell at: * sam@tunnelvisionlabs.com */ package org.tvl.goworks.editor.go.parser; import java.util.Collection; import java.util.HashSet; import java.util.Set; import org.antlr.netbeans.editor.text.DocumentSnapshot; import org.antlr.v4.runtime.CharStream; import org.antlr.v4.runtime.ParserRuleContext; import org.antlr.v4.runtime.RuleContext; import org.antlr.v4.runtime.RuleDependencies; import org.antlr.v4.runtime.RuleDependency; import org.antlr.v4.runtime.Token; import org.antlr.v4.runtime.TokenStream; import org.antlr.v4.runtime.tree.RuleNode; import org.antlr.works.editor.antlr4.classification.DocumentSnapshotCharStream; import org.tvl.goworks.editor.go.highlighter.SemanticHighlighter; import org.tvl.goworks.editor.go.parser.generated.AbstractGoParser; import org.tvl.goworks.editor.go.parser.generated.GoParserBaseVisitor; /** * * @author Sam Harwell */ public class GoParser extends AbstractGoParser { private final Set<String> packageNames = new HashSet<>(); private DocumentSnapshot snapshot; public static final Set<String> PREDEFINED_FUNCTIONS_WITH_TYPE = new HashSet<String>() { { add("make"); add("new"); } }; public GoParser(TokenStream input) { super(input); CharStream charStream = input != null ? input.getTokenSource().getInputStream() : null; if (charStream instanceof DocumentSnapshotCharStream) { DocumentSnapshotCharStream documentSnapshotCharStream = (DocumentSnapshotCharStream) charStream; this.snapshot = documentSnapshotCharStream.getSnapshot(); } } @Override public void reset() { super.reset(); // must check for null because reset() is called from the Parser constructor, before fields of GoParser are initialized if (packageNames != null) { packageNames.clear(); } } @Override public void setInputStream(TokenStream input) { super.setInputStream(input); CharStream charStream = input != null ? input.getTokenSource().getInputStream() : null; if (charStream instanceof DocumentSnapshotCharStream) { DocumentSnapshotCharStream documentSnapshotCharStream = (DocumentSnapshotCharStream) charStream; this.snapshot = documentSnapshotCharStream.getSnapshot(); } else { this.snapshot = null; } } @Override protected void addPackageName(Token token) { String name = getPackageName(token); if (name == null || name.isEmpty()) { return; } packageNames.add(name); } @Override protected boolean isPackageName(Token token) { return token != null && packageNames.contains(token.getText()); } public Collection<? extends String> getPackageNames() { return packageNames; } public void setPackageNames(Collection<? extends String> names) { packageNames.clear(); packageNames.addAll(names); } @RuleDependency(recognizer = GoParser.class, rule = RULE_operand, version = 0) @Override protected boolean isLiteralAllowed(Token nextToken, OperandContext context) { if (nextToken.getType() != IDENTIFIER) { return true; } for (ParserRuleContext current = context; current != null; current = current.getParent()) { Boolean allowed = CompositeLiteralAllowedVisitor.INSTANCE.visit(current); if (allowed == null) { continue; } return allowed; } return true; } @Override protected boolean isBuiltInMethodName(Token token) { return token != null && SemanticHighlighter.PREDEFINED_FUNCTIONS.contains(token.getText()); } @Override protected boolean isBuiltInMethodWithType(Token token) { return token != null && PREDEFINED_FUNCTIONS_WITH_TYPE.contains(token.getText()); } protected static final class CompositeLiteralAllowedVisitor extends GoParserBaseVisitor<Boolean> { protected static final CompositeLiteralAllowedVisitor INSTANCE = new CompositeLiteralAllowedVisitor(); @RuleDependency(recognizer = GoParser.class, rule = RULE_expression, version = 1) @Override public Boolean visitChildren(RuleNode node) { RuleContext ruleContext = node.getRuleContext(); if (ruleContext instanceof ExpressionContext) { return visitAnyExpression((ExpressionContext) ruleContext); } return super.visitChildren(node); } @Override protected Boolean defaultResult() { return null; } @Override protected boolean shouldVisitNextChild(RuleNode node, Boolean currentResult) { return false; } @RuleDependencies({ @RuleDependency(recognizer = GoParser.class, rule = RULE_expression, version = 1), @RuleDependency(recognizer = GoParser.class, rule = RULE_exprSwitchStmt, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_arrayLength, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_elementNameOrIndex, version = 1), @RuleDependency(recognizer = GoParser.class, rule = RULE_channel, version = 1), @RuleDependency(recognizer = GoParser.class, rule = RULE_incDecStmt, version = 1), @RuleDependency(recognizer = GoParser.class, rule = RULE_ifStmt, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_condition, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_rangeClause, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_recvStmt, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_recvExpr, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_deferStmt, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_expressionList, version = 1), @RuleDependency(recognizer = GoParser.class, rule = RULE_operand, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_value, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_conversion, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_expressionStmt, version = 1), @RuleDependency(recognizer = GoParser.class, rule = RULE_sendStmt, version = 1), @RuleDependency(recognizer = GoParser.class, rule = RULE_simpleStmt, version = 1), @RuleDependency(recognizer = GoParser.class, rule = RULE_typeSwitchGuard, version = 0), @RuleDependency(recognizer = GoParser.class, rule = RULE_goStmt, version = 0), }) private Boolean visitAnyExpression(ExpressionContext ctx) { ParserRuleContext parent = ctx.getParent(); if (parent == null) { return null; } switch (parent.getRuleIndex()) { case RULE_exprSwitchStmt: case RULE_arrayLength: case RULE_channel: case RULE_incDecStmt: case RULE_ifStmt: case RULE_condition: case RULE_rangeClause: case RULE_recvStmt: case RULE_recvExpr: case RULE_deferStmt: return false; case RULE_elementNameOrIndex: case RULE_expressionList: case RULE_operand: case RULE_value: case RULE_conversion: case RULE_expressionStmt: case RULE_sendStmt: case RULE_typeSwitchGuard: case RULE_goStmt: return true; // this one is needed due to explicit left factoring of expression // into simpleStmt, and this is called before the parse tree is // restored to the intended shape case RULE_simpleStmt: return true; case RULE_expression: if (parent instanceof SelectorExprContext || parent instanceof IndexExprContext || parent instanceof SliceExprContext || parent instanceof TypeAssertionExprContext) { return true; } else if (parent instanceof UnaryExprContext) { UnaryExprContext unaryParent = (UnaryExprContext) parent; if (unaryParent.op != null) { switch (unaryParent.op.getType()) { case Amp: // address of, but still has to be in a valid context return null; default: return false; } } // not building parse trees, assume was a valid op return true; } else if (parent instanceof CompareExprContext) { CompareExprContext compareParent = (CompareExprContext) parent; if (compareParent.op != null) { switch (compareParent.op.getType()) { case EqualEqual: case BangEqual: // equality comparison is allowed, but still has to be in a valid context return null; default: return false; } } // not building parse trees, assume was a valid op return true; } return false; } return null; } } }