android.databinding.tool.ExpressionParser Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of compiler Show documentation
The annotation processor for Data Binding. Generates binding classes for runtime.
The newest version!
/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.databinding.tool;

import org.antlr.v4.runtime.ANTLRInputStream;
import org.antlr.v4.runtime.BaseErrorListener;
import org.antlr.v4.runtime.CommonTokenStream;
import org.antlr.v4.runtime.ParserRuleContext;
import org.antlr.v4.runtime.RecognitionException;
import org.antlr.v4.runtime.Recognizer;
import org.antlr.v4.runtime.Token;
import org.antlr.v4.runtime.tree.ErrorNode;
import org.antlr.v4.runtime.tree.ParseTreeListener;
import org.antlr.v4.runtime.tree.TerminalNode;

import android.databinding.parser.BindingExpressionLexer;
import android.databinding.parser.BindingExpressionParser;
import android.databinding.tool.expr.Expr;
import android.databinding.tool.expr.ExprModel;
import android.databinding.tool.processing.ErrorMessages;
import android.databinding.tool.store.Location;
import android.databinding.tool.util.L;
import android.databinding.tool.util.Preconditions;

import com.android.annotations.Nullable;

import java.util.ArrayList;
import java.util.List;

public class ExpressionParser {
    final ExprModel mModel;
    final ExpressionVisitor visitor;

    public ExpressionParser(ExprModel model) {
        mModel = model;
        visitor = new ExpressionVisitor(mModel);
    }

    public Expr parse(String input, @Nullable Location locationInFile, BindingTarget target) {
        ANTLRInputStream inputStream = new ANTLRInputStream(input);
        BindingExpressionLexer lexer = new BindingExpressionLexer(inputStream);
        CommonTokenStream tokenStream = new CommonTokenStream(lexer);
        final BindingExpressionParser parser = new BindingExpressionParser(tokenStream);
        visitor.setBindingTarget(target);
        parser.addErrorListener(new BaseErrorListener() {
            @Override
            public void syntaxError(Recognizer recognizer, Object offendingSymbol, int line,
                    int charPositionInLine, String msg, RecognitionException e) {
                L.e(ErrorMessages.SYNTAX_ERROR, msg);
            }
        });
        BindingExpressionParser.BindingSyntaxContext root = parser.bindingSyntax();
        try {
            mModel.setCurrentLocationInFile(locationInFile);
            visitor.setParseTreeListener(new ParseTreeListener() {
                List mStack = new ArrayList();
                @Override
                public void visitTerminal(TerminalNode node) {
                }

                @Override
                public void visitErrorNode(ErrorNode node) {
                }

                @Override
                public void enterEveryRule(ParserRuleContext ctx) {
                    mStack.add(ctx);
                    mModel.setCurrentParserContext(ctx);
                }

                @Override
                public void exitEveryRule(ParserRuleContext ctx) {
                    Preconditions.check(ctx == mStack.get(mStack.size() - 1),
                            "Inconsistent exit from context. Received %s, expecting %s",
                            ctx.toInfoString(parser),
                            mStack.get(mStack.size() - 1).toInfoString(parser));
                    mStack.remove(mStack.size() - 1);
                    if (mStack.size() > 0) {
                        mModel.setCurrentParserContext(mStack.get(mStack.size() - 1));
                    } else {
                        mModel.setCurrentParserContext(null);
                    }
                }
            });
            return root.accept(visitor);
        } finally {
            mModel.setCurrentLocationInFile(null);
        }
    }

    public ExprModel getModel() {
        return mModel;
    }
}