com.amihaiemil.eoyaml.BaseYamlNode Maven / Gradle / Ivy

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YAML for Java 8 and above. Very similar to the JSON-P api.
The newest version!
/**
 * Copyright (c) 2016-2024, Mihai Emil Andronache
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this
 *  list of conditions and the following disclaimer.
 *  Redistributions in binary form must reproduce the above copyright notice,
 *  this list of conditions and the following disclaimer in the documentation
 *  and/or other materials provided with the distribution.
 * Neither the name of the copyright holder nor the names of its
 *  contributors may be used to endorse or promote products derived from
 *  this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
package com.amihaiemil.eoyaml;

import com.amihaiemil.eoyaml.exceptions.YamlPrintException;
import com.amihaiemil.eoyaml.exceptions.YamlReadingException;

import java.io.IOException;
import java.io.StringWriter;

/**
 * Base YAML Node. This is the first class in the hierarchy
 * for any kind of YAML node.
 *
 * So far, the purpose of this base class is to hide methods that should
 * be applicable to all types of YamlNode and which we do not want
 * to make public on the YamlNode interface.
 *
 * @author Mihai Andronache ([email protected])
 * @version $Id: e2db5f75ced07d8140d9fca390d2ef043243985e $
 * @since 4.0.0
 */
abstract class BaseYamlNode implements YamlNode {

    /**
     * Print it as block with disregard to whether it came
     * from JSON/Flow-Style or not.
     */
    private final boolean alwaysPrintBlock;

    /**
     * Ctor.
     */
    BaseYamlNode() {
        this(false);
    }

    /**
     * Ctor.
     * @param alwaysPrintBlock Print it as block with disregard to whether it
     *  came from JSON/Flow-Style or not.
     */
    BaseYamlNode(final boolean alwaysPrintBlock) {
        this.alwaysPrintBlock = alwaysPrintBlock;
    }

    @Override
    public final Scalar asScalar()
        throws YamlReadingException, ClassCastException {
        return this.asClass(Scalar.class, Node.SCALAR);
    }

    @Override
    public final YamlMapping asMapping()
        throws YamlReadingException, ClassCastException {
        return this.asClass(YamlMapping.class, Node.MAPPING);
    }

    @Override
    public final YamlSequence asSequence()
        throws YamlReadingException, ClassCastException {
        return this.asClass(YamlSequence.class, Node.SEQUENCE);
    }

    @Override
    public final YamlStream asStream()
        throws YamlReadingException, ClassCastException {
        return this.asClass(YamlStream.class, Node.STREAM);
    }

    @Override
    public final  T asClass(final Class clazz,
                                                final Node type)
        throws YamlReadingException, ClassCastException {
        if (this.type() != type) {
            throw new YamlReadingException(
                "The YamlNode is not a " + clazz.getSimpleName() + '!');
        }
        return clazz.cast(this);
    }

    /**
     * Print this YamlNode using a StringWriter to create its
     * String representation.
     * @return String print of this YamlNode.
     * @throws YamlPrintException If there is any I/O problem
     *  when printing the YAML.
     *
     */
    @Override
    public final String toString() {
        final StringWriter writer = new StringWriter();
        final YamlPrinter printer = new RtYamlPrinter(
            writer, this.alwaysPrintBlock
        );
        try {
            printer.print(this);
            return writer.toString();
        } catch (final IOException ex) {
            throw new YamlPrintException(
                "IOException when printing YAML", ex
            );
        }
    }
}