org.coursera.courier.grammar.ParseUtils.java Source code

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Here is the source code for org.coursera.courier.grammar.ParseUtils.java

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/*
 * Copyright 2015 Coursera Inc.
 *
 * 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 org.coursera.courier.grammar;

import org.antlr.v4.runtime.FailedPredicateException;
import org.antlr.v4.runtime.IntStream;
import org.antlr.v4.runtime.Parser;
import org.antlr.v4.runtime.ParserRuleContext;
import org.antlr.v4.runtime.RecognitionException;
import org.antlr.v4.runtime.Recognizer;
import org.apache.commons.lang3.StringEscapeUtils;

import java.io.IOException;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.Iterator;
import java.util.List;

public class ParseUtils {
    public static String extractMarkdown(String schemaDoc) {
        return unescapeDocstring(stripMargin(schemaDoc.substring(3, schemaDoc.length() - 2)).trim());
    }

    private static String unescapeDocstring(String escaped) {
        // unescape "/*" and "*/"
        String commentUnescaped = escaped.replace("/*", "/*").replace("*/", "*/");
        return StringEscapeUtils.unescapeHtml4(commentUnescaped);
    }

    public static String extractString(String stringLiteral) {
        return StringEscapeUtils.unescapeJson(stringLiteral.substring(1, stringLiteral.length() - 1));
    }

    public static String stripMargin(String schemadoc) {
        char marginChar = '*';
        StringBuilder buf = new StringBuilder();
        for (String line : schemadoc.split("\n")) {
            int len = line.length();
            int index = 0;
            while (index < len && line.charAt(index) <= ' ') {
                index++;
            }

            if (index < len && line.charAt(index) == marginChar) {
                buf.append(line.substring(index + 1));
            } else {
                buf.append(line);
            }
        }
        return buf.toString();
    }

    public static String unescapeIdentifier(String identifier) {
        return identifier.replaceAll("`", "");
    }

    public static String join(List<CourierParser.IdentifierContext> identifiers) {
        StringBuilder stringBuilder = new StringBuilder();
        Iterator<CourierParser.IdentifierContext> iter = identifiers.iterator();
        while (iter.hasNext()) {
            stringBuilder.append(iter.next().value);
            if (iter.hasNext()) {
                stringBuilder.append(".");
            }
        }
        return stringBuilder.toString();
    }

    // There must be a better way.
    public static Number toNumber(String string) {
        BigDecimal value = new BigDecimal(string);
        try {
            long l = value.longValueExact();
            int i = (int) l;
            if ((long) i == l) {
                return i;
            } else {
                return l;
            }
        } catch (ArithmeticException e) {
            double d = value.doubleValue();
            if (BigDecimal.valueOf(d).equals(value)) {
                float f = (float) d;
                if ((double) f == d) {
                    return (float) d;
                } else {
                    return d;
                }
            } else {
                return null;
            }
        }
    }
}