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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright (c) 2013, 2017 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.json;

import org.glassfish.json.api.BufferPool;

import javax.json.*;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.Writer;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.Map;

/**
 * JsonWriter impl using generator.
 *
 * @author Jitendra Kotamraju
 */
class JsonWriterImpl implements JsonWriter {

    private final JsonGeneratorImpl generator;
    private boolean writeDone;
    private final NoFlushOutputStream os;

    JsonWriterImpl(Writer writer, BufferPool bufferPool) {
        this(writer, false, bufferPool);
    }

    JsonWriterImpl(Writer writer, boolean prettyPrinting, BufferPool bufferPool) {
        generator = prettyPrinting
                ? new JsonPrettyGeneratorImpl(writer, bufferPool)
                : new JsonGeneratorImpl(writer, bufferPool);
        os = null;
    }

    JsonWriterImpl(OutputStream out, BufferPool bufferPool) {
        this(out, StandardCharsets.UTF_8, false, bufferPool);
    }

    JsonWriterImpl(OutputStream out, boolean prettyPrinting, BufferPool bufferPool) {
        this(out, StandardCharsets.UTF_8, prettyPrinting, bufferPool);
    }

    JsonWriterImpl(OutputStream out, Charset charset,
                   boolean prettyPrinting, BufferPool bufferPool) {
        // Decorating the given stream, so that buffered contents can be
        // written without actually flushing the stream.
        this.os = new NoFlushOutputStream(out);
        generator = prettyPrinting
                ? new JsonPrettyGeneratorImpl(os, charset, bufferPool)
                : new JsonGeneratorImpl(os, charset, bufferPool);
    }

    @Override
    public void writeArray(JsonArray array) {
        if (writeDone) {
            throw new IllegalStateException(JsonMessages.WRITER_WRITE_ALREADY_CALLED());
        }
        writeDone = true;
        generator.writeStartArray();
        for(JsonValue value : array) {
            generator.write(value);
        }
        generator.writeEnd();
        // Flush the generator's buffered contents. This won't work for byte
        // streams as intermediary OutputStreamWriter buffers.
        generator.flushBuffer();
        // Flush buffered contents but not the byte stream. generator.flush()
        // does OutputStreamWriter#flushBuffer (package private) and underlying
        // byte stream#flush(). Here underlying stream's flush() is no-op.
        if (os != null) {
            generator.flush();
        }
    }

    @Override
    public void writeObject(JsonObject object) {
        if (writeDone) {
            throw new IllegalStateException(JsonMessages.WRITER_WRITE_ALREADY_CALLED());
        }
        writeDone = true;
        generator.writeStartObject();
        for(Map.Entry e : object.entrySet()) {
            generator.write(e.getKey(), e.getValue());
        }
        generator.writeEnd();
        // Flush the generator's buffered contents. This won't work for byte
        // streams as intermediary OutputStreamWriter buffers.
        generator.flushBuffer();
        // Flush buffered contents but not the byte stream. generator.flush()
        // does OutputStreamWriter#flushBuffer (package private) and underlying
        // byte stream#flush(). Here underlying stream's flush() is no-op.
        if (os != null) {
            generator.flush();
        }
    }

    @Override
    public void write(JsonStructure value) {
        if (value instanceof JsonArray) {
            writeArray((JsonArray)value);
        } else {
            writeObject((JsonObject)value);
        }
    }

    @Override
    public void write(JsonValue value) {
        switch (value.getValueType()) {
            case OBJECT:
                writeObject((JsonObject) value);
                return;
            case ARRAY:
                writeArray((JsonArray) value);
                return;
            default:
                if (writeDone) {
                    throw new IllegalStateException(JsonMessages.WRITER_WRITE_ALREADY_CALLED());
                }
                writeDone = true;
                generator.write(value);
                generator.flushBuffer();
                if (os != null) {
                    generator.flush();
                }
        }
    }

    @Override
    public void close() {
        writeDone = true;
        generator.close();
    }

    private static final class NoFlushOutputStream extends FilterOutputStream {
        public NoFlushOutputStream(OutputStream out) {
            super(out);
        }

        @Override
        public void write(byte b[], int off, int len) throws IOException {
            out.write(b, off ,len);
        }

        @Override
        public void flush() {
            // no-op
        }
    }

}