com.xylocore.copybook.generator.parser.CopybookProcessor.java Source code

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Here is the source code for com.xylocore.copybook.generator.parser.CopybookProcessor.java

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//
//   Copyright 2013 The Palantir Corporation
//
//   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 com.xylocore.copybook.generator.parser;

import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Paths;

import org.antlr.v4.runtime.ANTLRInputStream;
import org.antlr.v4.runtime.CommonTokenStream;
import org.antlr.v4.runtime.tree.ParseTree;
import org.antlr.v4.runtime.tree.ParseTreeWalker;

import com.xylocore.copybook.generator.Environment;
import com.xylocore.copybook.generator.domain.Copybook;
import com.xylocore.copybook.generator.domain.config.Metadata;

/**
 * FILLIN
 * 
 * @author      Eric R. Medley
 */

public class CopybookProcessor {
    //
    // Class implementation
    //

    /**
     * FILLIN
     * 
     * @param       aEnvironment
     * 
     * @return
     */
    public Copybook process(Environment aEnvironment) {
        try (InputStream myInputStream = openCopybookSource(aEnvironment)) {
            Metadata myMetadata = aEnvironment.getMetadata();
            CopybookInputStream myCIS = new CopybookInputStream(myInputStream, myMetadata.getRightMarginLimit());
            ANTLRInputStream myInput = new ANTLRInputStream(myCIS);
            CopybookLexer myLexer = new CopybookLexer(myInput);
            CommonTokenStream myTokenStream = new CommonTokenStream(myLexer);
            CopybookParser myParser = new CopybookParser(myTokenStream);
            ParseTree myParseTree = myParser.copybook();
            ParseTreeWalker myWalker = new ParseTreeWalker();
            CopybookTransformationListener myListener = new CopybookTransformationListener(aEnvironment);

            myWalker.walk(myListener, myParseTree);

            return myListener.getCopybook();
        } catch (IOException myIOException) {
            // TODO: implement better exception processing
            throw new RuntimeException(myIOException);
        }
    }

    /**
     * FILLIN
     * 
     * @param       aEnvironment
     * 
     * @return
     * 
     * @exception   IOException
     */
    private InputStream openCopybookSource(Environment aEnvironment) throws IOException {
        assert aEnvironment != null;

        Metadata myMetadata = aEnvironment.getMetadata();
        String myFilename = myMetadata.getCopybookFilename();
        InputStream myInputStream;

        if (myFilename.equals("-")) {
            myInputStream = System.in;
        } else {
            myInputStream = Files.newInputStream(Paths.get(myFilename));
        }

        return myInputStream;
    }
}