org.openmdx.base.rest.stream.RestTarget Maven / Gradle / Ivy
/*
* ====================================================================
* Project: openMDX/Core, http://www.openmdx.org/
* Description: REST Target
* Owner: OMEX AG, Switzerland, http://www.omex.ch
* ====================================================================
*
* This software is published under the BSD license as listed below.
*
* Copyright (c) 2013, OMEX AG, Switzerland
* 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 openMDX team 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 OWNER 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.
*
* ------------------
*
* This product includes software developed by other organizations as
* listed in the NOTICE file.
*/
package org.openmdx.base.rest.stream;
import java.io.IOException;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;
import org.openmdx.base.naming.Path;
import org.openmdx.base.naming.URLEncoder;
import org.openmdx.base.rest.spi.Target;
import org.openmdx.kernel.exception.BasicException;
import org.openmdx.kernel.id.UUIDs;
/**
* Abstract Target
*/
public abstract class RestTarget implements Target {
/**
* Constructor
*
* @param uri
*/
protected RestTarget(String uri) {
this.urlEncoder = new URLEncoder(uri);
}
/**
* Map a cause to an XMLStreamException
*
* @param exception
* the exception to be mapped
*
* @return an XMLStreamException
*/
protected static XMLStreamException toXMLStreamException(
Exception exception
) {
BasicException cause = BasicException.toExceptionStack(exception);
return new XMLStreamException(cause.getMessage(), cause);
}
/**
* The URL encoder
*/
private final URLEncoder urlEncoder;
/**
* The XML output stream
*/
private XMLStreamWriter writer;
/**
* Retrieve the base URI
*
* @return the HREF prefix
*/
protected String getBase() {
return this.urlEncoder.getContextURL();
}
/**
* Terminates and flushes the document
*/
@Override
public void close(
) throws IOException {
if (this.writer != null) try {
this.writer.writeEndDocument();
this.writer.flush();
this.writer = null;
} catch (XMLStreamException exception) {
throw new IOException("Flushing failed", exception);
}
}
/**
* Discard the writer
*/
protected void reset(){
this.writer = null;
}
/**
* Create an XML stream writer
*
* @return a new XML stream writer
*
* @throws XMLStreamException
*/
protected abstract XMLStreamWriter newWriter()
throws XMLStreamException;
/**
* Retrieve an XML Stream Write
*
* @return an XML Stream Writer for an open document
*
* @throws XMLStreamException
*/
protected XMLStreamWriter getWriter()
throws XMLStreamException {
if (this.writer == null) {
this.writer = newWriter();
this.writer.writeStartDocument();
}
return this.writer;
}
/**
* Retrieve the href URL for a given resource identifier
*
* @param xri
* the resource identifier
*
* @return the href URL for the given XRI
*/
protected String toURL(
Path xri
) {
return xri != null ? urlEncoder.encode(xri) : getBase() + "/!" + UUIDs.newUUID();
}
}