org.primordion.xholon.io.json.JsonStrWriter.java Source code

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Here is the source code for org.primordion.xholon.io.json.JsonStrWriter.java

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/* Xholon Runtime Framework - executes event-driven & dynamic applications
 * Copyright (C) 2010 Ken Webb
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1
 * of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
 */

package org.primordion.xholon.io.json;

import com.google.gwt.core.client.JsonUtils;

//import java.io.Writer;

//import javax.xml.stream.XMLStreamException;

//import org.codehaus.jettison.AbstractXMLStreamWriter;
//import org.codehaus.jettison.mapped.Configuration;
//import org.codehaus.jettison.mapped.MappedNamespaceConvention;
//import org.codehaus.jettison.mapped.MappedXMLStreamWriter;
import org.primordion.xholon.io.xml.XmlWriter;

/**
 * A concrete class that knows how to write JSON through a Stax writer.
 * @author <a href="mailto:ken@primordion.com">Ken Webb</a>
 * @see <a href="http://www.primordion.com/Xholon">Xholon Project website</a>
 * @since 0.8.1 (Created on May 3, 2010)
 */
public class JsonStrWriter extends XmlWriter {

    private static final String WRITERNAME = "JsonStrWriter";

    //private AbstractXMLStreamWriter streamWriter = null;
    protected StringBuilder sb = null;

    /**
     * By default, Jettison prepends a @ to each attribute,
     * I assume to distinguish attributes from elements.
     */
    private boolean suppressAtAttributes = true;

    /**
     * default constructor
     */
    public JsonStrWriter() {
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#createNew(java.lang.Object)
     */
    public void createNew(Object out) {
        /*Configuration config = new Configuration();
        config.setSupressAtAttributes(suppressAtAttributes); // don't prepend @ to each attribute
        MappedNamespaceConvention con = new MappedNamespaceConvention(config);
        streamWriter = new MappedXMLStreamWriter(con, (Writer)out);*/
        if (out instanceof StringBuilder) {
            sb = (StringBuilder) out;
        }
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeStartDocument()
     */
    public void writeStartDocument() {
        /*try {
        streamWriter.writeStartDocument();
        } catch (XMLStreamException e) {
        e.printStackTrace();
        }*/
        sb.append("{");
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeEndDocument()
     */
    public void writeEndDocument() {
        /*try {
           streamWriter.writeEndDocument();
        } catch (XMLStreamException e) {
           e.printStackTrace();
        }*/

        // JSON does not allow dangling commas
        // if existing last char == ',' then replace that last char
        int len = sb.length();
        if (sb.charAt(len - 1) == ',') {
            sb.setCharAt(len - 1, '}');
        } else {
            sb.append("}");
        }
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeStartElement(java.lang.String, java.lang.String, java.lang.String)
     */
    public void writeStartElement(String prefix, String localName, String namespaceURI) {
        /*try {
           streamWriter.writeStartElement(prefix, localName, namespaceURI);
        } catch (XMLStreamException e) {
           e.printStackTrace();
        }*/
        writeStartElement(localName);
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeStartElement(java.lang.String)
     */
    public void writeStartElement(String name) {
        /*try {
           streamWriter.writeStartElement(name);
        } catch (XMLStreamException e) {
           e.printStackTrace();
        }*/
        sb.append("\"").append(name).append("\":{");
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeEndElement(java.lang.String, java.lang.String)
     */
    public void writeEndElement(String name, String namespaceURI) {
        writeEndElement(name);
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeEndElement(String name)
     */
    public void writeEndElement(String name) {
        /*try {
           streamWriter.writeEndElement();
        } catch (XMLStreamException e) {
           e.printStackTrace();
        }*/

        // JSON does not allow dangling commas
        // if existing last char == ',' then replace that last char
        int len = sb.length();
        if (sb.charAt(len - 1) == ',') {
            sb.setCharAt(len - 1, '}');
            sb.append(',');
        } else {
            sb.append("},");
        }
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeNamespace(java.lang.String, java.lang.String)
     */
    public void writeNamespace(String prefix, String namespaceURI) {
        /*try {
           streamWriter.writeNamespace(prefix, namespaceURI);
        } catch (XMLStreamException e) {
           e.printStackTrace();
        }*/
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeAttribute(java.lang.String, java.lang.String)
     */
    public void writeAttribute(String name, String value) {
        /*try {
           streamWriter.writeAttribute(name, value);
        } catch (XMLStreamException e) {
           e.printStackTrace();
        }*/

        // ex: "connector": "ancestor::PetriNet/Places/C"
        if ("Val".equalsIgnoreCase(name) && !isShouldWriteVal()) {
            return;
        }
        if ("AllPorts".equalsIgnoreCase(name) && !isShouldWriteAllPorts()) {
            return;
        }
        sb.append("\"").append(name).append("\":").append(JsonUtils.escapeValue(value)) // Returns a quoted, escaped JSON String.
                .append(",");
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeText(java.lang.String)
     */
    public void writeText(String text) {
        /*try {
           streamWriter.writeCharacters(text);
        } catch (XMLStreamException e) {
           e.printStackTrace();
        }*/
        sb.append("\"").append("Text").append("\":").append(JsonUtils.escapeValue(text)) // Returns a quoted, escaped JSON String.
                .append(",");
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#writeComment(java.lang.String)
     */
    public void writeComment(String data) {
        /*try {
           streamWriter.writeComment(data);
        } catch (XMLStreamException e) {
           e.printStackTrace();
        }*/
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#getWriterName()
     */
    public String getWriterName() {
        return WRITERNAME;
    }

    /*
     * @see org.primordion.xholon.io.xml.XmlWriter#flush()
     */
    public void flush() {
        /*try {
           streamWriter.flush();
        } catch (XMLStreamException e) {
           e.printStackTrace();
        }*/
    }

    public boolean isSuppressAtAttributes() {
        return suppressAtAttributes;
    }

    public void setSuppressAtAttributes(boolean suppressAtAttributes) {
        this.suppressAtAttributes = suppressAtAttributes;
    }
}