JsonXMLOutputFactory.java

/*
 * Copyright 2011, 2012 Odysseus Software GmbH
 *
 * 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.apache.synapse.commons.staxon.core.json;

import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.util.Arrays;

import javax.xml.namespace.QName;
import javax.xml.stream.FactoryConfigurationError;
import javax.xml.stream.XMLEventWriter;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;

import org.apache.synapse.commons.staxon.core.base.AbstractXMLOutputFactory;
import org.apache.synapse.commons.staxon.core.event.SimpleXMLEventWriter;
import org.apache.synapse.commons.staxon.core.json.stream.JsonStreamFactory;
import org.apache.synapse.commons.staxon.core.json.stream.JsonStreamTarget;
import org.apache.synapse.commons.staxon.core.json.stream.util.RemoveRootTarget;
import org.apache.synapse.commons.staxon.core.json.stream.util.CustomRegexMatchReplaceIgnoreAutoPrimitiveTarget;
import org.apache.synapse.commons.staxon.core.json.stream.util.CustomRegexIgnoreAutoPrimitiveTarget;
import org.apache.synapse.commons.staxon.core.json.stream.util.AutoArrayTarget;
import org.apache.synapse.commons.staxon.core.json.stream.util.AutoPrimitiveTarget;

/**
 * XML output factory for streaming to JSON.
 */
public class JsonXMLOutputFactory extends AbstractXMLOutputFactory {
    /**
     * <p>Start/end arrays automatically?</p>
     * <p/>
     * <p>The default value is <code>false</code>.</p>
     */
    public static final String PROP_AUTO_ARRAY = "JsonXMLOutputFactory.autoArray";

    /**
     * <p>Convert element text to JSON primitives (number, boolean, null) automatically?</p>
     * <p/>
     * <p>The default value is <code>false</code>.</p>
     */
    public static final String PROP_AUTO_PRIMITIVE = "JsonXMLOutputFactory.autoPrimitive";

    /**
     * <p>Whether to use the {@link JsonXMLStreamConstants#MULTIPLE_PI_TARGET}
     * processing instruction target to trigger an array start.
     * If <code>true</code>, a PI is used to inform the writer to begin an array,
     * passing the name of following multiple elements as data.
     * The writer will close arrays automatically.</p>
     * <p/>
     * <p>Note that the element given in the PI may be written zero times,
     * indicating an empty array.</p>
     * <p/>
     * <p>The default value is true.</p>
     */
    public static final String PROP_MULTIPLE_PI = "JsonXMLOutputFactory.multiplePI";

    /**
     * <p>JSON documents may have have multiple root properties. However,
     * XML requires a single root element. This property takes the name
     * of a "virtual" root element, which will be removed from the stream
     * when writing.</p>
     * <p/>
     * <p>The default value is <code>null</code>.</p>
     */
    public static final String PROP_VIRTUAL_ROOT = "JsonXMLOutputFactory.virtualRoot";

    /**
     * <p>Namespace prefix separator.</p>
     * <p/>
     * <p>The default value is <code>':'</code>.</p>
     */
    public static final String PROP_NAMESPACE_SEPARATOR = "JsonXMLOutputFactory.namespaceSeparator";

    /**
     * <p>Whether to write namespace declarations.</p>
     * <p/>
     * <p>The default value is <code>true</code>.</p>
     */
    public static final String PROP_NAMESPACE_DECLARATIONS = "JsonXMLOutputFactory.namespaceDeclarations";

    /**
     * <p>Format output for better readability?</p>
     * <p/>
     * <p>The default value is <code>false</code>.</p>
     */
    public static final String PROP_PRETTY_PRINT = "JsonXMLOutputFactory.prettyPrint";


    /**
     * <p>Convert element text to JSON primitives with ignore given regex (number, boolean, null) automatically?</p>
     *
     * <p>The default value is <code>null</code>.</p>
     */
    public static final String PROP_CUSTOM_REGEX = "JsonXMLOutputFactory.customRegex";

    public static final String PROP_CUSTOM_REPLACE_REGEX = "JsonXMLOutputFactory.customReplaceRegex";

    public static final String PROP_CUSTOM_REPLACE_SEQUENCE = "JsonXMLOutputFactory.customReplaceSequence";


    private JsonStreamFactory streamFactory;
    private boolean multiplePI;
    private QName virtualRoot;
    private boolean autoArray;
    private boolean autoPrimitive;
    private boolean prettyPrint;
    private char namespaceSeparator;
    private boolean namespaceDeclarations;
    private String customRegex;
    private String customReplaceRegex;
    private String customReplaceSequence;
    private boolean xmlNilReadWriteEnabled;

    public JsonXMLOutputFactory() throws FactoryConfigurationError {
        this(JsonXMLConfig.DEFAULT);
    }

    public JsonXMLOutputFactory(JsonStreamFactory streamFactory) {
        this(JsonXMLConfig.DEFAULT, streamFactory);
    }

    public JsonXMLOutputFactory(JsonXMLConfig config) throws FactoryConfigurationError {
        this(config, JsonStreamFactory.newFactory());
    }

    public JsonXMLOutputFactory(JsonXMLConfig config, JsonStreamFactory streamFactory) {
        this.multiplePI = config.isMultiplePI();
        this.virtualRoot = config.getVirtualRoot();
        this.autoArray = config.isAutoArray();
        this.autoPrimitive = config.isAutoPrimitive();
        this.prettyPrint = config.isPrettyPrint();
        this.namespaceSeparator = config.getNamespaceSeparator();
        this.namespaceDeclarations = config.isNamespaceDeclarations();
        this.streamFactory = streamFactory;
        this.customRegex= config.getCustomRegex();
        this.customReplaceRegex = config.getCustomReplaceRegex();
        this.customReplaceSequence = config.getCustomReplaceSequence();
        this.xmlNilReadWriteEnabled = config.isReadWriteXmlNil();

		/*
         * initialize standard properties
		 */
        super.setProperty(IS_REPAIRING_NAMESPACES, config.isRepairingNamespaces());
    }

    private JsonStreamTarget decorate(JsonStreamTarget target) {
        if (virtualRoot != null) {
            target = new RemoveRootTarget(target, virtualRoot, namespaceSeparator);
        }
        if (autoArray) {
            target = new AutoArrayTarget(target);
        }
        if (autoPrimitive) {
            if (customRegex != null) {
                target = new CustomRegexIgnoreAutoPrimitiveTarget(target, false, customRegex);
            } else if (customReplaceRegex != null) {
                target = new CustomRegexMatchReplaceIgnoreAutoPrimitiveTarget(target, false, customReplaceRegex, customReplaceSequence);
            } else {
                target = new AutoPrimitiveTarget(target, false);
            }
        }
        return target;
    }

    @Override
    public JsonXMLStreamWriter createXMLStreamWriter(OutputStream stream, String encoding) throws XMLStreamException {
        try {
            return createXMLStreamWriter(new OutputStreamWriter(stream, encoding));
        } catch (UnsupportedEncodingException e) {
            throw new XMLStreamException(e);
        }
    }

    @Override
    public JsonXMLStreamWriter createXMLStreamWriter(Writer stream) throws XMLStreamException {
        boolean repairNamespaces = Boolean.TRUE.equals(getProperty(IS_REPAIRING_NAMESPACES));
        try {
            return new JsonXMLStreamWriter(decorate(streamFactory.createJsonStreamTarget(stream, prettyPrint)),
                    repairNamespaces, multiplePI, namespaceSeparator, namespaceDeclarations, xmlNilReadWriteEnabled);
        } catch (IOException e) {
            throw new XMLStreamException(e);
        }
    }

    @Override
    public JsonXMLStreamWriter createXMLStreamWriter(OutputStream stream) throws XMLStreamException {
        boolean repairNamespaces = Boolean.TRUE.equals(getProperty(IS_REPAIRING_NAMESPACES));
        try {
            return new JsonXMLStreamWriter(decorate(streamFactory.createJsonStreamTarget(stream, prettyPrint)),
                    repairNamespaces, multiplePI, namespaceSeparator, namespaceDeclarations, xmlNilReadWriteEnabled);
        } catch (IOException e) {
            throw new XMLStreamException(e);
        }
    }

    @Override
    public XMLEventWriter createXMLEventWriter(XMLStreamWriter writer) throws XMLStreamException {
        return new SimpleXMLEventWriter(writer);
    }

    @Override
    public boolean isPropertySupported(String name) {
        return super.isPropertySupported(name)
                || Arrays.asList(PROP_AUTO_ARRAY, PROP_MULTIPLE_PI, PROP_VIRTUAL_ROOT, PROP_NAMESPACE_SEPARATOR, PROP_NAMESPACE_DECLARATIONS, PROP_PRETTY_PRINT, PROP_CUSTOM_REPLACE_REGEX, PROP_CUSTOM_REPLACE_SEQUENCE).contains(name);
    }

    @Override
    public Object getProperty(String name) throws IllegalArgumentException {
        if (super.isPropertySupported(name)) {
            return super.getProperty(name);
        } else { // proprietary properties
            if (PROP_AUTO_ARRAY.equals(name)) {
                return Boolean.valueOf(autoArray);
            } else if (PROP_AUTO_PRIMITIVE.equals(name)) {
                return Boolean.valueOf(autoPrimitive);
            } else if (PROP_MULTIPLE_PI.equals(name)) {
                return Boolean.valueOf(multiplePI);
            } else if (PROP_VIRTUAL_ROOT.equals(name)) {
                return virtualRoot;
            } else if (PROP_PRETTY_PRINT.equals(name)) {
                return Boolean.valueOf(prettyPrint);
            } else if (PROP_NAMESPACE_SEPARATOR.equals(name)) {
                return namespaceSeparator;
            } else if (PROP_NAMESPACE_DECLARATIONS.equals(name)) {
                return Boolean.valueOf(namespaceDeclarations);
            } else if (PROP_CUSTOM_REGEX.equals(name)) {
                return customRegex;
            } else if (PROP_CUSTOM_REPLACE_REGEX.equals(name)) {
                return customReplaceRegex;
            } else if (PROP_CUSTOM_REPLACE_SEQUENCE.equals(name)) {
                return customReplaceSequence;
            } else {
                throw new IllegalArgumentException("Unsupported property: " + name);
            }
        }
    }

    @Override
    public void setProperty(String name, Object value) throws IllegalArgumentException {
        if (super.isPropertySupported(name)) {
            super.setProperty(name, value);
        } else { // proprietary properties
            if (PROP_AUTO_ARRAY.equals(name)) {
                autoArray = ((Boolean) value).booleanValue();
            } else if (PROP_AUTO_PRIMITIVE.equals(name)) {
                autoPrimitive = ((Boolean) value).booleanValue();
            } else if (PROP_MULTIPLE_PI.equals(name)) {
                multiplePI = ((Boolean) value).booleanValue();
            } else if (PROP_VIRTUAL_ROOT.equals(name)) {
                virtualRoot = value instanceof String ? QName.valueOf((String) value) : (QName) value;
            } else if (PROP_PRETTY_PRINT.equals(name)) {
                prettyPrint = ((Boolean) value).booleanValue();
            } else if (PROP_NAMESPACE_SEPARATOR.equals(name)) {
                namespaceSeparator = (Character) value;
            } else if (PROP_NAMESPACE_DECLARATIONS.equals(name)) {
                namespaceDeclarations = ((Boolean) value).booleanValue();
            } else if (PROP_CUSTOM_REGEX.equals(name) && value instanceof String) {
                customRegex = (String) value;
            } else if (PROP_CUSTOM_REPLACE_REGEX.equals(name) && value instanceof String) {
                customReplaceRegex = (String) value;
            } else if (PROP_CUSTOM_REPLACE_SEQUENCE.equals(name) && value instanceof String) {
                customReplaceSequence = (String) value;
            } else {
                throw new IllegalArgumentException("Unsupported property: " + name);
            }
        }
    }
}