com.igormaznitsa.jcp.expression.functions.FunctionSTR2JAVA.java Source code

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Here is the source code for com.igormaznitsa.jcp.expression.functions.FunctionSTR2JAVA.java

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/* 
 * Copyright 2014 Igor Maznitsa (http://www.igormaznitsa.com).
 *
 * 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.igormaznitsa.jcp.expression.functions;

import javax.annotation.Nonnull;

import com.igormaznitsa.jcp.context.PreprocessorContext;
import com.igormaznitsa.jcp.expression.Value;
import com.igormaznitsa.jcp.expression.ValueType;
import com.igormaznitsa.jcp.utils.PreprocessorUtils;

import org.apache.commons.lang3.StringEscapeUtils;

import com.igormaznitsa.meta.annotation.MustNotContainNull;

/**
 * The class implements escape function handler to escape strings to be used in java.
 *
 * @author Igor Maznitsa (igor.maznitsa@igormaznitsa.com)
 */
public final class FunctionSTR2JAVA extends AbstractFunction {

    private static final ValueType[][] ARG_TYPES = new ValueType[][] { { ValueType.STRING, ValueType.BOOLEAN } };

    @Override
    @Nonnull
    public String getName() {
        return "str2java";
    }

    @Nonnull
    public Value executeStrBool(@Nonnull final PreprocessorContext context, @Nonnull final Value source,
            @Nonnull final Value splitAndQuoteLines) {
        if (splitAndQuoteLines.asBoolean()) {
            final boolean endsWithNextLine = source.asString().endsWith("\n");
            final String[] splitted = PreprocessorUtils.splitForCharAndHoldEmptyLine(source.asString(), '\n');
            final StringBuilder result = new StringBuilder(source.asString().length() * 2);
            final String nextLineChars = PreprocessorUtils.getNextLineCodes();

            int index = 0;
            for (final String s : splitted) {
                final boolean last = ++index == splitted.length;
                if (result.length() > 0) {
                    result.append(nextLineChars).append('+');
                }
                result.append('\"').append(StringEscapeUtils.escapeJava(s));
                if (last) {
                    result.append(endsWithNextLine ? "\\n\"" : "\"");
                } else {
                    result.append("\\n\"");
                }
            }
            return Value.valueOf(result.toString());
        } else {
            return Value.valueOf(StringEscapeUtils.escapeJava(source.asString()));
        }
    }

    @Override
    public int getArity() {
        return 2;
    }

    @Override
    @Nonnull
    @MustNotContainNull
    public ValueType[][] getAllowedArgumentTypes() {
        return ARG_TYPES;
    }

    @Override
    @Nonnull
    public String getReference() {
        return "escapes a string to be compatible with java";
    }

    @Override
    @Nonnull
    public ValueType getResultType() {
        return ValueType.STRING;
    }

}