gcc/libjava/javax/xml/parsers/SAXParserFactory.java

/* SAXParserFactory.java -- 
   Copyright (C) 2004, 2005  Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath 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
General Public License for more details.

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Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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independent module, the terms and conditions of the license of that
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this exception to your version of the library, but you are not
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package javax.xml.parsers;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.IOException;
import java.util.Properties;
import javax.xml.validation.Schema;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;

/**
 * Factory for obtaining SAX parsers.
 * Instances of this class are <em>not</em> guaranteed to be thread safe.
 *
 * @author (a href='mailto:dog@gnu.org'>Chris Burdess</a)
 */
public abstract class SAXParserFactory
{

  private boolean validating;
  private boolean namespaceAware;
  private Schema schema;
  private boolean xIncludeAware;

  protected SAXParserFactory()
  {
  }

  /**
   * Creates a new factory instance.
   * The implementation class to load is the first found in the following
   * locations:
   * <ol>
   * <li>the <code>javax.xml.parsers.SAXParserFactory</code> system
   * property</li>
   * <li>the above named property value in the
   * <code><i>$JAVA_HOME</i>/lib/jaxp.properties</code> file</li>
   * <li>the class name specified in the
   * <code>META-INF/services/javax.xml.parsers.SAXParserFactory</code>
   * system resource</li>
   * <li>the default factory class</li>
   * </ol>
   */
  public static SAXParserFactory newInstance()
    throws FactoryConfigurationError
  {
    ClassLoader loader = Thread.currentThread().getContextClassLoader();
    if (loader == null)
      {
        loader = SAXParserFactory.class.getClassLoader();
      }
    String className = null;
    int count = 0;
    do
      {
        className = getFactoryClassName(loader, count++);
        if (className != null)
          {
            try
              {
                Class t = (loader != null) ? loader.loadClass(className) :
                  Class.forName(className);
                return (SAXParserFactory) t.newInstance();
              }
            catch (ClassNotFoundException e)
              {
                className = null;
              }
            catch (Exception e)
              {
                throw new FactoryConfigurationError(e,
                     "error instantiating class " + className);
              }
          }
      }
    while (className == null && count < 3);
    return new gnu.xml.aelfred2.JAXPFactory();
  }

  private static String getFactoryClassName(ClassLoader loader, int attempt)
  {
    final String propertyName = "javax.xml.parsers.SAXParserFactory";
    switch (attempt)
      {
        case 0:
          return System.getProperty(propertyName);
        case 1:
          try
            {
              File file = new File(System.getProperty("java.home"));
              file = new File(file, "lib");
              file = new File(file, "jaxp.properties");
              InputStream in = new FileInputStream(file);
              Properties props = new Properties();
              props.load(in);
              in.close();
              return props.getProperty(propertyName);
            }
          catch (IOException e)
            {
              return null;
            }
        case 2:
          try
            {
              String serviceKey = "/META-INF/services/" + propertyName;
              InputStream in = (loader != null) ?
                 loader.getResourceAsStream(serviceKey) :
                SAXParserFactory.class.getResourceAsStream(serviceKey);
              if (in != null)
                {
                  BufferedReader r =
                     new BufferedReader(new InputStreamReader(in));
                  String ret = r.readLine();
                  r.close();
                  return ret;
                }
            }
          catch (IOException e)
            {
            }
          return null;
        default:
          return null;
      }
  }

  /**
   * Creates a new parser instance using the currently specified factory
   * configuration.
   * @exception ParserConfigurationException if the specified configuration
   * is not supported
   */
  public abstract SAXParser newSAXParser()
    throws ParserConfigurationException, SAXException;

  /**
   * Sets whether parsers obtained from this factory will be XML Namespace
   * aware.
   */
  public void setNamespaceAware(boolean awareness)
  {
    namespaceAware = awareness;
  }

  /**
   * Sets whether parsers obtained from this factory will validate their
   * input.
   */
  public void setValidating(boolean validating)
  {
    this.validating = validating;
  }

  /**
   * Indicates whether parsers obtained from this factory will be XML
   * Namespace aware.
   */
  public boolean isNamespaceAware()
  {
    return namespaceAware;
  }

  /**
   * Indicates whether parsers obtained from this factory will validate
   * their input.
   */
  public boolean isValidating()
  {
    return validating;
  }

  /**
   * Sets the specified feature for SAX2 parsers obtained from this factory.
   * @param name the feature name
   * @param value the featurevalue
   */
  public abstract void setFeature(String name, boolean value) 
    throws ParserConfigurationException, SAXNotRecognizedException, 
           SAXNotSupportedException;

  /**
   * Returns the specified feature for SAX2 parsers obtained from this
   * factory.
   * @param name the feature name
   */
  public abstract boolean getFeature(String name) 
    throws ParserConfigurationException, SAXNotRecognizedException, 
           SAXNotSupportedException;

  // -- JAXP 1.3 methods --

  /**
   * Returns the schema.
   * @since 1.3
   * @see #setSchema
   */
  public Schema getSchema()
  {
    return schema;
  }

  /**
   * Sets the schema.
   * @since 1.3
   * @see #getSchema
   */
  public void setSchema(Schema schema)
  {
    this.schema = schema;
  }

  /**
   * Indicates whether parsers obtained from this factory will be XInclude
   * aware.
   * @since 1.3
   */
  public boolean isXIncludeAware()
  {
    return xIncludeAware;
  }

  /**
   * Sets whether parsers obtained from this factory will be XInclude aware.
   * @since 1.3
   */
  public void setXIncludeAware(boolean state)
  {
    xIncludeAware = state;
  }

}