modules/core/src/flex/messaging/io/amf/AbstractAmfInput.java - flex-blazeds - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You 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 flex.messaging.io.amf;

 import java.io.DataInputStream;
 import java.io.IOException;
 import java.io.InputStream;

 import flex.messaging.MessageException;
 import flex.messaging.io.AbstractProxy;
 import flex.messaging.io.BeanProxy;
 import flex.messaging.io.ClassAliasRegistry;
 import flex.messaging.io.PropertyProxy;
 import flex.messaging.io.PropertyProxyRegistry;
 import flex.messaging.io.SerializationContext;
 import flex.messaging.io.SerializationException;
 import flex.messaging.util.ClassUtil;
 import flex.messaging.util.XMLUtil;

 /**
  * A deserializer of AMF protocol data.
  *
  * @see ActionMessageOutput
  *
  */
 public abstract class AbstractAmfInput extends AmfIO implements ActionMessageInput
 {
     /**
      * This is the initial capacity that will be used for AMF arrays, vectors, etc.
      * that have length greater than 1024.
      */
     public static final int INITIAL_COLLECTION_CAPACITY = 1024;

     /**
      * This is the default max String length (25MB).
      */
     public static final int DEFAULT_MAX_STRING_BYTES = 26214400;
     public static final String STRING_MAX_STRING_BYTES = "max-string-bytes";

     protected BeanProxy beanProxy = new BeanProxy();
     protected DataInputStream in = null;
     protected int maxStringBytes = DEFAULT_MAX_STRING_BYTES;

     /**
      * Construct a deserializer without connecting it to an input stream.
      * @param context serialization parameters.
      */
     public AbstractAmfInput(SerializationContext context)
     {
         super(context);

         readMaxStringBytes();
     }

     /**
      * Internal use
      *
      */
     public void setInputStream(InputStream in)
     {
         this.in = new DataInputStream(in);
     }

     protected Object stringToDocument(String xml)
     {
         // FIXME: Temporary workaround for bug 194815
         if (xml != null && xml.indexOf('<') == -1)
             return xml;

         // Validation performed in XMLUtil#stringToDocument.
         return XMLUtil.stringToDocument(xml, !(context.legacyXMLNamespaces),
                 context.allowXmlExternalEntityExpansion);
     }

     /**
      * A utility method that is used by subclasses to perform max-string-bytes
      * checks. By default, max-string-bytes is limited to 25MB for security
      * but this can be changed via JVM option called max-string-bytes.
      *
      * @param utflen The UTF string length to check.
      * @throws <tt>SerializationException</tt> if max-string-bytes has been exceeded.
      */
     protected void checkUTFLength(int utflen)
     {
         if (utflen > maxStringBytes)
         {
             // Error deserializing the string with length ''{0}'', it exceeds the max-string-bytes limit of ''{1}''.
             SerializationException ex = new SerializationException();
             ex.setMessage(10314, new Object[] {utflen, maxStringBytes});
             throw ex;
         }
     }

     /**
      * Internal use. Common logic for creating an object for AMF0 and AMF3. Used from
      * Amf0Input.readObjectValue() and Amf3Input.readScriptObject().
      * This method is responsible for resolving class aliases, creating and
      * registering a property proxy and instantiating an instance of the desired class.
      * The params array is used as a holder for parameter values that are updated or
      * created in this method, but are needed by its callers.
      * @param params array of values that may be updated by this method.
      *               [0] - String className - the name or alias of the class to create
      *               [1] - PropertyProxy proxy
      * @return an instance of the appropriate object for deserialization
      *
      */
     protected Object createObjectInstance(Object[] params)
     {
         String className = (String)params[0];

         // Check for any registered class aliases
         String aliasedClass = ClassAliasRegistry.getRegistry().getClassName(className);
         if (aliasedClass != null)
         {
             className = aliasedClass;
             params[0] = className; //update the params array so that callers get this change
         }

         Object object = null;
         PropertyProxy proxy = null;

         if (className != null && className.startsWith(">")) // Handle [RemoteClass] (no server alias)
         {
             object = createDefaultASObject(className);
         }
         else if (className != null && className.length() > 0 && (context.instantiateTypes || className.startsWith("flex.")))
         {
             // otherwise attempt to create an instance if we have a className
             Class<?> desiredClass = null;
             try
             {
                 desiredClass = AbstractProxy.getClassFromClassName(className);
             }
             catch (MessageException me)
             {
                 // Type not found and don't want to use ASObject for the missing type.
                 if (!(me.getCode().startsWith(MessageException.CODE_SERVER_RESOURCE_UNAVAILABLE)
                         && context.createASObjectForMissingType))
                 {
                     throw me; // Rethrow.
                 }
                 // if we didn't rethrow the exception, the default ASObject will be created further down.
             }

             // Type exists. Create either default instance of desiredClass or an instance from a registered proxy.
             if (desiredClass != null)
             {
                 proxy = PropertyProxyRegistry.getRegistry().getProxyAndRegister(desiredClass);
                 if (proxy == null)
                 {
                     object = ClassUtil.createDefaultInstance(desiredClass, null, true /*validate*/);
                 }
                 else
                 {
                     object = proxy.createInstance(className); // Validation is performed in the proxy.
                 }
             }
         }

         // if we still don't have an object, create an ASObject with what we have for className (can be null)
         if (object == null)
             object = createDefaultASObject(className);

         // if proxy wasn't created, create one based on the new instance.
         if (proxy == null)
             proxy = PropertyProxyRegistry.getProxyAndRegister(object);

         params[1] = proxy; //update the params array so that callers get the proxy

         return object;
     }

     /**
      * Internal use. Convenience method for creating an ASObject and assigning it a type
      * @param type named type for the ASObject or null
      * @return a new instance of ASObject
      *
      */
     protected ASObject createDefaultASObject(String type)
     {
         ASObject object = (ASObject) ClassUtil.createDefaultInstance(ASObject.class, null, true /*validate*/);
         if (type != null && type.length() > 0)
             object.setType(type);
         return object;
     }

     /**
      *
      */
     protected void readMaxStringBytes()
     {
         // See if a JVM option is specified for max-string-bytes.
         String maxStringBytes = null;
         try
         {
             maxStringBytes = System.getProperty(STRING_MAX_STRING_BYTES);
         }
         catch (SecurityException se)
         {
             // Ignore and use the default.
         }

         if (maxStringBytes == null)
             return;

         try
         {
             this.maxStringBytes = Integer.parseInt(maxStringBytes);
         }
         catch (NumberFormatException ignore)
         {
             // Ignore and use the default.
         }
     }

     //
     // java.io.ObjectInput IMPLEMENTATIONS
     //

     /** {@inheritDoc} */
     public int available() throws IOException
     {
         return in.available();
     }

     /** {@inheritDoc} */
     public void close() throws IOException
     {
         in.close();
     }

     /** {@inheritDoc} */
     public int read() throws IOException
     {
         return in.read();
     }

     /** {@inheritDoc} */
     public int read(byte[] bytes) throws IOException
     {
         return in.read(bytes);
     }

     /** {@inheritDoc} */
     public int read(byte[] bytes, int offset, int length) throws IOException
     {
         return in.read(bytes, offset, length);
     }

     /** {@inheritDoc} */
     public long skip(long n) throws IOException
     {
         return in.skip(n);
     }

     /** {@inheritDoc} */
     public int skipBytes(int n) throws IOException
     {
         return in.skipBytes(n);
     }

     //
     // java.io.DataInput IMPLEMENTATIONS
     //

     /** {@inheritDoc} */
     public boolean readBoolean() throws IOException
     {
         return in.readBoolean();
     }

     /** {@inheritDoc} */
     public byte readByte() throws IOException
     {
         return in.readByte();
     }

     /** {@inheritDoc} */
     public char readChar() throws IOException
     {
         return in.readChar();
     }

     /** {@inheritDoc} */
     public double readDouble() throws IOException
     {
         return in.readDouble();
     }

     /** {@inheritDoc} */
     public float readFloat() throws IOException
     {
         return in.readFloat();
     }

     /** {@inheritDoc} */
     public void readFully(byte[] bytes) throws IOException
     {
         in.readFully(bytes);
     }

     /** {@inheritDoc} */
     public void readFully(byte[] bytes, int offset, int length) throws IOException
     {
         in.readFully(bytes, offset, length);
     }

     /** {@inheritDoc} */
     public int readInt() throws IOException
     {
         return in.readInt();
     }

     /**
      *  Reads the next line of text from the input stream.
      * @deprecated
      */
     public String readLine() throws IOException
     {
         return in.readLine();
     }

     /** {@inheritDoc} */
     public long readLong() throws IOException
     {
         return in.readLong();
     }

     /** {@inheritDoc} */
     public short readShort() throws IOException
     {
         return in.readShort();
     }

     /** {@inheritDoc} */
     public int readUnsignedByte() throws IOException
     {
         return in.readUnsignedByte();
     }

     /** {@inheritDoc} */
     public int readUnsignedShort() throws IOException
     {
         return in.readUnsignedShort();
     }

     /** {@inheritDoc} */
     public String readUTF() throws IOException
     {
         return in.readUTF();
     }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You 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 flex.messaging.io.amf;

	import java.io.DataInputStream;
	import java.io.IOException;
	import java.io.InputStream;

	import flex.messaging.MessageException;
	import flex.messaging.io.AbstractProxy;
	import flex.messaging.io.BeanProxy;
	import flex.messaging.io.ClassAliasRegistry;
	import flex.messaging.io.PropertyProxy;
	import flex.messaging.io.PropertyProxyRegistry;
	import flex.messaging.io.SerializationContext;
	import flex.messaging.io.SerializationException;
	import flex.messaging.util.ClassUtil;
	import flex.messaging.util.XMLUtil;

	/**
	* A deserializer of AMF protocol data.
	*
	* @see ActionMessageOutput
	*
	*/
	public abstract class AbstractAmfInput extends AmfIO implements ActionMessageInput
	{
	/**
	* This is the initial capacity that will be used for AMF arrays, vectors, etc.
	* that have length greater than 1024.
	*/
	public static final int INITIAL_COLLECTION_CAPACITY = 1024;

	/**
	* This is the default max String length (25MB).
	*/
	public static final int DEFAULT_MAX_STRING_BYTES = 26214400;
	public static final String STRING_MAX_STRING_BYTES = "max-string-bytes";

	protected BeanProxy beanProxy = new BeanProxy();
	protected DataInputStream in = null;
	protected int maxStringBytes = DEFAULT_MAX_STRING_BYTES;

	/**
	* Construct a deserializer without connecting it to an input stream.
	* @param context serialization parameters.
	*/
	public AbstractAmfInput(SerializationContext context)
	{
	super(context);

	readMaxStringBytes();
	}

	/**
	* Internal use
	*
	*/
	public void setInputStream(InputStream in)
	{
	this.in = new DataInputStream(in);
	}

	protected Object stringToDocument(String xml)
	{
	// FIXME: Temporary workaround for bug 194815
	if (xml != null && xml.indexOf('<') == -1)
	return xml;

	// Validation performed in XMLUtil#stringToDocument.
	return XMLUtil.stringToDocument(xml, !(context.legacyXMLNamespaces),
	context.allowXmlExternalEntityExpansion);
	}

	/**
	* A utility method that is used by subclasses to perform max-string-bytes
	* checks. By default, max-string-bytes is limited to 25MB for security
	* but this can be changed via JVM option called max-string-bytes.
	*
	* @param utflen The UTF string length to check.
	* @throws <tt>SerializationException</tt> if max-string-bytes has been exceeded.
	*/
	protected void checkUTFLength(int utflen)
	{
	if (utflen > maxStringBytes)
	{
	// Error deserializing the string with length ''{0}'', it exceeds the max-string-bytes limit of ''{1}''.
	SerializationException ex = new SerializationException();
	ex.setMessage(10314, new Object[] {utflen, maxStringBytes});
	throw ex;
	}
	}

	/**
	* Internal use. Common logic for creating an object for AMF0 and AMF3. Used from
	* Amf0Input.readObjectValue() and Amf3Input.readScriptObject().
	* This method is responsible for resolving class aliases, creating and
	* registering a property proxy and instantiating an instance of the desired class.
	* The params array is used as a holder for parameter values that are updated or
	* created in this method, but are needed by its callers.
	* @param params array of values that may be updated by this method.
	* [0] - String className - the name or alias of the class to create
	* [1] - PropertyProxy proxy
	* @return an instance of the appropriate object for deserialization
	*
	*/
	protected Object createObjectInstance(Object[] params)
	{
	String className = (String)params[0];

	// Check for any registered class aliases
	String aliasedClass = ClassAliasRegistry.getRegistry().getClassName(className);
	if (aliasedClass != null)
	{
	className = aliasedClass;
	params[0] = className; //update the params array so that callers get this change
	}

	Object object = null;
	PropertyProxy proxy = null;

	if (className != null && className.startsWith(">")) // Handle [RemoteClass] (no server alias)
	{
	object = createDefaultASObject(className);
	}
	else if (className != null && className.length() > 0 && (context.instantiateTypes \|\| className.startsWith("flex.")))
	{
	// otherwise attempt to create an instance if we have a className
	Class<?> desiredClass = null;
	try
	{
	desiredClass = AbstractProxy.getClassFromClassName(className);
	}
	catch (MessageException me)
	{
	// Type not found and don't want to use ASObject for the missing type.
	if (!(me.getCode().startsWith(MessageException.CODE_SERVER_RESOURCE_UNAVAILABLE)
	&& context.createASObjectForMissingType))
	{
	throw me; // Rethrow.
	}
	// if we didn't rethrow the exception, the default ASObject will be created further down.
	}

	// Type exists. Create either default instance of desiredClass or an instance from a registered proxy.
	if (desiredClass != null)
	{
	proxy = PropertyProxyRegistry.getRegistry().getProxyAndRegister(desiredClass);
	if (proxy == null)
	{
	object = ClassUtil.createDefaultInstance(desiredClass, null, true /validate/);
	}
	else
	{
	object = proxy.createInstance(className); // Validation is performed in the proxy.
	}
	}
	}

	// if we still don't have an object, create an ASObject with what we have for className (can be null)
	if (object == null)
	object = createDefaultASObject(className);

	// if proxy wasn't created, create one based on the new instance.
	if (proxy == null)
	proxy = PropertyProxyRegistry.getProxyAndRegister(object);

	params[1] = proxy; //update the params array so that callers get the proxy

	return object;
	}

	/**
	* Internal use. Convenience method for creating an ASObject and assigning it a type
	* @param type named type for the ASObject or null
	* @return a new instance of ASObject
	*
	*/
	protected ASObject createDefaultASObject(String type)
	{
	ASObject object = (ASObject) ClassUtil.createDefaultInstance(ASObject.class, null, true /validate/);
	if (type != null && type.length() > 0)
	object.setType(type);
	return object;
	}

	/**
	*
	*/
	protected void readMaxStringBytes()
	{
	// See if a JVM option is specified for max-string-bytes.
	String maxStringBytes = null;
	try
	{
	maxStringBytes = System.getProperty(STRING_MAX_STRING_BYTES);
	}
	catch (SecurityException se)
	{
	// Ignore and use the default.
	}

	if (maxStringBytes == null)
	return;

	try
	{
	this.maxStringBytes = Integer.parseInt(maxStringBytes);
	}
	catch (NumberFormatException ignore)
	{
	// Ignore and use the default.
	}
	}

	//
	// java.io.ObjectInput IMPLEMENTATIONS
	//

	/** {@inheritDoc} */
	public int available() throws IOException
	{
	return in.available();
	}

	/** {@inheritDoc} */
	public void close() throws IOException
	{
	in.close();
	}

	/** {@inheritDoc} */
	public int read() throws IOException
	{
	return in.read();
	}

	/** {@inheritDoc} */
	public int read(byte[] bytes) throws IOException
	{
	return in.read(bytes);
	}

	/** {@inheritDoc} */
	public int read(byte[] bytes, int offset, int length) throws IOException
	{
	return in.read(bytes, offset, length);
	}

	/** {@inheritDoc} */
	public long skip(long n) throws IOException
	{
	return in.skip(n);
	}

	/** {@inheritDoc} */
	public int skipBytes(int n) throws IOException
	{
	return in.skipBytes(n);
	}

	//
	// java.io.DataInput IMPLEMENTATIONS
	//

	/** {@inheritDoc} */
	public boolean readBoolean() throws IOException
	{
	return in.readBoolean();
	}

	/** {@inheritDoc} */
	public byte readByte() throws IOException
	{
	return in.readByte();
	}

	/** {@inheritDoc} */
	public char readChar() throws IOException
	{
	return in.readChar();
	}

	/** {@inheritDoc} */
	public double readDouble() throws IOException
	{
	return in.readDouble();
	}

	/** {@inheritDoc} */
	public float readFloat() throws IOException
	{
	return in.readFloat();
	}

	/** {@inheritDoc} */
	public void readFully(byte[] bytes) throws IOException
	{
	in.readFully(bytes);
	}

	/** {@inheritDoc} */
	public void readFully(byte[] bytes, int offset, int length) throws IOException
	{
	in.readFully(bytes, offset, length);
	}

	/** {@inheritDoc} */
	public int readInt() throws IOException
	{
	return in.readInt();
	}

	/**
	* Reads the next line of text from the input stream.
	* @deprecated
	*/
	public String readLine() throws IOException
	{
	return in.readLine();
	}

	/** {@inheritDoc} */
	public long readLong() throws IOException
	{
	return in.readLong();
	}

	/** {@inheritDoc} */
	public short readShort() throws IOException
	{
	return in.readShort();
	}

	/** {@inheritDoc} */
	public int readUnsignedByte() throws IOException
	{
	return in.readUnsignedByte();
	}

	/** {@inheritDoc} */
	public int readUnsignedShort() throws IOException
	{
	return in.readUnsignedShort();
	}

	/** {@inheritDoc} */
	public String readUTF() throws IOException
	{
	return in.readUTF();
	}
	}