/*
* JBoss, Home of Professional Open Source.
*
* See the LEGAL.txt file distributed with this work for information regarding copyright ownership and licensing.
*
* See the AUTHORS.txt file distributed with this work for a full listing of individual contributors.
*/
package org.teiid.designer.common.xsd;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;
import org.teiid.core.designer.TeiidDesignerException;
/**
* @since 8.0
*/
public class XsdHeaderReader {
private static final String XML_DECLARATION_PREFIX_STRING = "<?xml version="; //$NON-NLS-1$
// ==================================================================================
// C O N S T R U C T O R S
// ==================================================================================
public XsdHeaderReader() {
}
// ==================================================================================
// P U B L I C M E T H O D S
// ==================================================================================
public static XsdHeader readHeader( InputStream istream ) throws TeiidDesignerException {
XsdHeaderReader reader = new XsdHeaderReader();
return reader.read(istream);
}
public static XsdHeader readHeader( File file ) throws TeiidDesignerException {
XsdHeaderReader reader = new XsdHeaderReader();
return reader.read(file);
}
/**
* Read only the <XMI.header> section of the file and return the <code>XMIHeader</code> object representing its contents
*
* @param istream the InputStream from which we read the header
* @return the XMIHeader object representing the contents of this section
* @throws TeiidDesignerException if there is an error reading from the stream
*/
public XsdHeader read( InputStream istream ) throws TeiidDesignerException {
if (istream == null) {
// TODO: ADD I18n ??
final String msg = "XsdHeaderReader.The_InputStream_reference_may_not_be_null._1"; //$NON-NLS-1$
throw new IllegalArgumentException(msg);
}
DefaultHandler handler = new TerminatingXsdHeaderContentHandler();
try {
Thread.currentThread().setContextClassLoader(XsdHeaderReader.class.getClassLoader());
SAXParserFactory spf = SAXParserFactory.newInstance();
spf.setNamespaceAware(true);
SAXParser parser = spf.newSAXParser();
parser.parse(new InputSource(istream), handler);
} catch (SAXException e) {
if (TerminatingXsdHeaderContentHandler.SCHEMA_FOUND_EXCEPTION_MESSAGE.equals(e.getMessage())) {
// The schema information was successfully read
} else if (TerminatingXsdHeaderContentHandler.SCHEMA_NOT_FOUND_EXCEPTION_MESSAGE.equals(e.getMessage())) {
// The file is probably an XML file but not an XSD file
return null;
} else if (e instanceof SAXParseException) {
// The file is probably a text file but not an XML file
return null;
}
} catch (IOException e) {
// The file is not a file that can be interpretted by the SAX parser
} catch (Throwable e) {
// TODO: ADD I18n ??
final String msg = "XsdHeaderReader.Error_in_parsing_file_1"; //$NON-NLS-1$
throw new TeiidDesignerException(e, msg);
}
return ((TerminatingXsdHeaderContentHandler)handler).getXsdHeader();
}
/**
* Read only the <XMI.header> section of the file and return the <code>XMIHeader</code> object representing its contents
*
* @param file the File from which we read the header
* @return the XMIHeader object representing the contents of this section
* @throws TeiidDesignerException if there is an error reading the file
*/
public XsdHeader read( File file ) throws TeiidDesignerException {
if (file == null) {
// TODO: ADD I18n ??
final String msg = "XsdHeaderReader.The_file_reference_may_not_be_null_2"; //$NON-NLS-1$
throw new IllegalArgumentException(msg);
}
if (!file.exists()) {
//final Object[] params = new Object[] {file};
// TODO: ADD I18n ??
final String msg = "XsdHeaderReader.The_file_0_does_not_exist_and_therefore_cannot_be_read._3"; //$NON-NLS-1$
throw new IllegalArgumentException(msg);
}
if (!file.canRead()) {
//final Object[] params = new Object[] {file};
// TODO: ADD I18n ??
final String msg = "XsdHeaderReader.The_file_0_does_not_have_read_privileges._4"; //$NON-NLS-1$
throw new IllegalArgumentException(msg);
}
// If the file does not start with an XML declaration tag ...
if (!isXmlFile(file)) {
return null;
}
// Attempt to read the XML file and interpret it as an XMI file
FileInputStream fis = null;
BufferedInputStream bis = null;
try {
fis = new FileInputStream(file);
bis = new BufferedInputStream(fis);
return read(bis);
} catch (FileNotFoundException e) {
// TODO: ADD I18n ??
final String msg = "XsdHeaderReader.Error_in_parsing_file_1"; //$NON-NLS-1$
throw new TeiidDesignerException(e, msg);
} finally {
if (bis != null) {
try {
bis.close();
} catch (IOException e) {
}
}
if (fis != null) {
try {
fis.close();
} catch (IOException e) {
}
}
}
}
// ==================================================================================
// P R I V A T E M E T H O D S
// ==================================================================================
private static boolean isXmlFile( File file ) {
FileInputStream fis = null;
try {
fis = new FileInputStream(file);
byte[] buf = new byte[32];
fis.read(buf);
if (new String(buf).startsWith(XML_DECLARATION_PREFIX_STRING)) {
return true;
}
} catch (IOException e) {
// do nothing
} finally {
if (fis != null) {
try {
fis.close();
} catch (IOException e) {
}
}
}
return false;
}
}