polyglot.util

Class TypeEncoder

java.lang.Object

polyglot.util.TypeEncoder

public class TypeEncoder
extends java.lang.Object

The TypeEncoder gives the ability to encode a polyglot Type as a Java string.

It uses a form of serialization to encode the Type into a byte stream and then converts the byte stream to a standard Java string.

The difference between the encoder and a normal serialization process is that in order to encode this type, we need to sever any links to other types in the current environment. So any ClassType other than the the type being encoded is replaced in the stream with a PlaceHolder that contains the name of the class. To aid in the decoding process, placeholders for member classes user their "mangled" name; non-member classes use their fully qualified name.

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	base64
protected int	depth
protected java.util.Map<java.lang.Object,java.lang.Object>	placeHolderCache
protected boolean	test
protected TypeSystem	ts
protected boolean	zip

Constructor Summary

Constructors

Constructor and Description
TypeEncoder(TypeSystem ts)

Method Summary

Methods

Modifier and Type	Method and Description
TypeObject	decode(java.lang.String s, java.lang.String name) Decode a serialized type object.
java.lang.String	encode(TypeObject t) Serialize a type object into a string.
TypeInputStream	ois(java.io.ByteArrayInputStream bais)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ts

protected TypeSystem ts

zip

protected final boolean zip

See Also:

Constant Field Values

base64

protected final boolean base64

See Also:

Constant Field Values

test

protected final boolean test

See Also:

Constant Field Values

placeHolderCache

protected java.util.Map<java.lang.Object,java.lang.Object> placeHolderCache

depth

protected int depth

Constructor Detail

TypeEncoder

public TypeEncoder(TypeSystem ts)

Method Detail

encode

public java.lang.String encode(TypeObject t)
                        throws java.io.IOException

Serialize a type object into a string.

Parameters:

t - The TypeObject to encode.

Returns:

String containing the encoded type object.

Throws:

java.io.IOException - If the encoding fails.

decode

public TypeObject decode(java.lang.String s,
                java.lang.String name)
                  throws java.io.InvalidClassException

Decode a serialized type object. If deserialization fails because a type could not be resolved, the method returns null. The calling pass should abort in that case.

Parameters:

s - String containing the encoded type object.

Returns:

The decoded TypeObject, or null if deserialization fails.

Throws:

java.io.InvalidClassException - If the string is malformed.

ois

public TypeInputStream ois(java.io.ByteArrayInputStream bais)
                    throws java.io.IOException

Throws:

java.io.IOException