org.smartfrog.sfcore.common
Class ContextImpl

java.lang.Object
  java.util.Dictionary
      java.util.Hashtable
          org.smartfrog.sfcore.common.OrderedHashtable
              org.smartfrog.sfcore.common.ContextImpl

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.util.Map, Context, Copying, MessageKeys, PrettyPrinting

public class ContextImpl
extends OrderedHashtable
implements Context, java.io.Serializable, PrettyPrinting

Implements the context interface. This implementation relies on the OrderedHashtable class in the Utilities, but another class can be used. The important thing for any implementation is the fact that the order in which entries are added to the context should be maintained even through the enumeration returning methods.

See Also:

Serialized Form

Field Summary

Fields inherited from class org.smartfrog.sfcore.common.OrderedHashtable

initCap, keysInc, loadFac, orderedKeys

Fields inherited from interface org.smartfrog.sfcore.common.MessageKeys

CANNOT_LINK_TO_PREDICATE, COMPONENT_TERMINATED, COPY_FAILED, COPY_SERIALIZE_FAILED, ERROR_NO_SECURITY_BUT_REQUIRED, ILLEGAL_BOOLEAN_PARAMETER, ILLEGAL_NUMERIC_PARAMETER, ILLEGAL_STRING_PARAMETER, ILLEGAL_VECTOR_PARAMETER, LIVENESS_SEND_FAILURE, LIVENESS_SEND_FAILURE_IN, MISSING_PARAMETER, MSG_CLASS_NOT_FOUND, MSG_CONNECT_ERR, MSG_CONT_OTHER_DEPLOY, MSG_DEPLOY_COMP_TERMINATED, MSG_DEPLOY_SUCCESS, MSG_DEPLOYWITH_PHASE_FAILED, MSG_DETACH_SUCCESS, MSG_DETACH_TERMINATE_SUCCESS, MSG_ERR_DEPLOY_FROM_URL, MSG_ERR_PARSE, MSG_ERR_RESOLVE_PHASE, MSG_ERR_SF_RUNNING, MSG_ERR_TERM, MSG_FAILED_INET_ADDRESS_LOOKUP, MSG_FAILED_TO_CONTACT_PARENT, MSG_FILE_NOT_FOUND, MSG_HOOK_ACTION_FAILED, MSG_ILLEGAL_ACCESS, MSG_ILLEGAL_CLASS_TYPE, MSG_ILLEGAL_CLASS_TYPE_EXPECTING_GOT, MSG_ILLEGAL_REFERENCE, MSG_INPUTSTREAM_NULL, MSG_INSTANTIATION_ERROR, MSG_INVALID_OBJECT_TYPE, MSG_INVOCATION_TARGET, MSG_LANG_NOT_FOUND, MSG_LIVENESS_START_FAILED, MSG_LOADING_URL, MSG_METHOD_NOT_FOUND, MSG_NON_REP_ATTRIB, MSG_NOT_COMPONENT_REFERENCE, MSG_NOT_FOUND_ATTRIBUTE, MSG_NOT_FOUND_REFERENCE, MSG_NOT_VALUE_REFERENCE, MSG_NULL_DEF_METHOD, MSG_NULL_URL, MSG_OBJECT_REGISTRATION_FAILED, MSG_PARENT_LOCATION_FAILED, MSG_PING_SUCCESS, MSG_RANDM_ERR, MSG_REMOTE_CONNECT_ERR, MSG_REPEATED_ATTRIBUTE, MSG_SF_DEAD, MSG_SF_READY, MSG_SF_TERMINATED, MSG_STACKTRACE_FOLLOWS, MSG_START_COMP_TERMINATED, MSG_TERMINATE_SUCCESS, MSG_UNHANDLED_EXCEPTION, MSG_UNKNOWN_HOST, MSG_UNRESOLVED_REFERENCE, MSG_UNRESOLVED_REFERENCE_IN, MSG_UPDATE_SUCCESS, MSG_URL_NOT_FOUND, MSG_URL_TO_PARSE_NOT_FOUND, MSG_WARNING_LIVENESS_ENABLED, MSG_WARNING_STACKTRACE_DISABLED, MSG_WARNING_STACKTRACE_ENABLED, ROOT_MUST_BE_COMPONENT, WARN_NO_SECURITY

Constructor Summary

ContextImpl()
Creates an empty context with default capacity.

ContextImpl(int cap, float load)
Constructs a context with initial capacity and a load trigger for expansion.

Method Summary

static java.lang.String	getBasicValueFor(java.lang.Object obj) Gets a given value in its String form.
java.lang.Object	keyFor(java.lang.Object value) Returns the first key for which the value is the given one.
java.lang.Object	sfAddAttribute(java.lang.Object name, java.lang.Object value) Adds an attribute to this context under given name.
java.lang.Object	sfAttributeFor(java.lang.Object value) Returns the first attribute which has a particular value in the table.
java.lang.Object	sfAttributeKeyFor(java.lang.Object value) Returns the attribute key given a value.
java.util.Iterator	sfAttributes() Returns an ordered iterator over the attribute names in the context.
boolean	sfContainsAttribute(java.lang.Object attribute) Returns true if the context contains attribute.
boolean	sfContainsValue(java.lang.Object value) Returns true if the context contains value.
java.lang.Object	sfRemoveAttribute(java.lang.Object name) Removes an attribute from this context.
java.lang.Object	sfReplaceAttribute(java.lang.Object name, java.lang.Object value) Replace named attribute in context.
java.lang.Object	sfResolveAttribute(java.lang.Object name) Find an attribute in this context.
java.util.Iterator	sfValues() Returns an ordered iterator over the values in the context.
protected static void	tabPad(java.io.Writer ps, int amount) Internal method to pad out a writer.
java.lang.String	toString() Returns a string representation of the component.
protected static void	writeBasicValueOn(java.io.Writer ps, int indent, java.lang.Object value) Writes a given value on a writer.
protected void	writeContextOn(java.io.Writer ps, int indent, java.util.Enumeration keys) Writes the context on a writer.
protected void	writeKeyOn(java.io.Writer ps, int indent, java.lang.Object key) Writes given attribute key on a writer.
void	writeOn(java.io.Writer ps) Writes this component description on a writer.
void	writeOn(java.io.Writer ps, int indent) Writes this component description on a writer.
protected void	writeValueOn(java.io.Writer ps, int indent, java.lang.Object value) Writes a given value on a writer.

Methods inherited from class org.smartfrog.sfcore.common.OrderedHashtable

clear, clone, copy, elements, keys, orderedAttributes, orderedValues, primPut, put, remove, remove, rename

Methods inherited from class java.util.Hashtable

contains, containsKey, containsValue, entrySet, equals, get, hashCode, isEmpty, keySet, putAll, rehash, size, values

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.smartfrog.sfcore.common.Context

clone, contains, containsKey, elements, get, isEmpty, keys, put, remove, rename, size

Methods inherited from interface org.smartfrog.sfcore.common.Copying

copy

Constructor Detail

ContextImpl

public ContextImpl()

Creates an empty context with default capacity.

ContextImpl

public ContextImpl(int cap,
                   float load)

Constructs a context with initial capacity and a load trigger for expansion.

Parameters:

cap - initial capacity

load - load capacity trigger

Method Detail

keyFor

public java.lang.Object keyFor(java.lang.Object value)

Returns the first key for which the value is the given one. Deprecated: replaced by sfAttributeFor(value);

Specified by:

keyFor in interface Context

Parameters:

value - value to look up

Returns:

key for value or null if not found

sfAttributeFor

public java.lang.Object sfAttributeFor(java.lang.Object value)

Returns the first attribute which has a particular value in the table.

Specified by:

sfAttributeFor in interface Context

Parameters:

value - value to find in table

Returns:

attibute object for value or null if none

sfContainsValue

public boolean sfContainsValue(java.lang.Object value)

Returns true if the context contains value. Replaces contains()

Specified by:

sfContainsValue in interface Context

Parameters:

value - object to check

Returns:

true if context contains value, false otherwise

sfContainsAttribute

public boolean sfContainsAttribute(java.lang.Object attribute)

Returns true if the context contains attribute. Replaces containsKey()

Specified by:

sfContainsAttribute in interface Context

Parameters:

attribute - to check

Returns:

true if context contains key, false otherwise

sfAttributes

public java.util.Iterator sfAttributes()

Returns an ordered iterator over the attribute names in the context. The remove operation of this Iterator won't affect the contents of Context

Specified by:

sfAttributes in interface Context

Returns:

iterator

sfValues

public java.util.Iterator sfValues()

Returns an ordered iterator over the values in the context. The remove operation of this Iterator won't affect the contents of Context

Specified by:

sfValues in interface Context

Returns:

iterator

sfResolveAttribute

public java.lang.Object sfResolveAttribute(java.lang.Object name)
                                    throws SmartFrogContextException

Find an attribute in this context.

Specified by:

sfResolveAttribute in interface Context

Parameters:

name - attribute key to resolve

Returns:

Object Reference

Throws:

SmartFrogContextException - failed to find attribute

sfAddAttribute

public java.lang.Object sfAddAttribute(java.lang.Object name,
                                       java.lang.Object value)
                                throws SmartFrogContextException

Adds an attribute to this context under given name.

Specified by:

sfAddAttribute in interface Context

Parameters:

name - name of attribute

value - value of attribute

Returns:

previous value for name or null if none

Throws:

SmartFrogContextException - when name or value are null or name already used

sfRemoveAttribute

public java.lang.Object sfRemoveAttribute(java.lang.Object name)
                                   throws SmartFrogContextException

Removes an attribute from this context.

Specified by:

sfRemoveAttribute in interface Context

Parameters:

name - of attribute to be removed

Returns:

removed attribute value if successfull or null if not

Throws:

SmartFrogContextException - when name is null

sfReplaceAttribute

public java.lang.Object sfReplaceAttribute(java.lang.Object name,
                                           java.lang.Object value)
                                    throws SmartFrogContextException

Replace named attribute in context. If attribute is not present it is added to the context.

Specified by:

sfReplaceAttribute in interface Context

Parameters:

name - of attribute to replace

value - value to add or replace

Returns:

the old value if present, null otherwise

Throws:

SmartFrogContextException - when name or value are null

sfAttributeKeyFor

public java.lang.Object sfAttributeKeyFor(java.lang.Object value)

Returns the attribute key given a value.

Specified by:

sfAttributeKeyFor in interface Context

Parameters:

value - value to look up key for

Returns:

key for attribute value or null if none

toString

public java.lang.String toString()

Returns a string representation of the component. This will give a description of the component which is parseable, and deployable again... Unless someone removed attributes which are essential to startup that is. Large description trees should be written out using writeOn since memory for large strings runs out quick!

Specified by:

toString in interface Context

Overrides:

toString in class java.util.Hashtable

Returns:

string representation of component

writeOn

public void writeOn(java.io.Writer ps)
             throws java.io.IOException

Writes this component description on a writer. Used by toString. Should be used instead of toString to write large descriptions to file, since memory can become a problem given the LONG strings created

Specified by:

writeOn in interface PrettyPrinting

Parameters:

ps - writer to write on

Throws:

java.io.IOException - failure while writing

writeOn

public void writeOn(java.io.Writer ps,
                    int indent)
             throws java.io.IOException

Writes this component description on a writer. Used by toString. Should be used instead of toString to write large descriptions to file, since memory can become a problem given the LONG strings created

Specified by:

writeOn in interface PrettyPrinting

Parameters:

ps - writer to write on

indent - the indent to use for printing offset

Throws:

java.io.IOException - failure while writing

writeContextOn

protected void writeContextOn(java.io.Writer ps,
                              int indent,
                              java.util.Enumeration keys)
                       throws java.io.IOException

Writes the context on a writer.

Parameters:

ps - writer to write on

indent - level

keys - enumeation over the keys of the context to write out

Throws:

java.io.IOException - failure while writing

writeKeyOn

protected void writeKeyOn(java.io.Writer ps,
                          int indent,
                          java.lang.Object key)
                   throws java.io.IOException

Writes given attribute key on a writer.

Parameters:

ps - writer to write on

indent - indent level

key - key to stringify

Throws:

java.io.IOException - failure while writing

writeValueOn

protected void writeValueOn(java.io.Writer ps,
                            int indent,
                            java.lang.Object value)
                     throws java.io.IOException

Writes a given value on a writer. Recognizes descriptions, strings and vectors of basic values and turns them into string representation. Default is to turn into string using normal toString() call

Parameters:

ps - writer to write on

indent - indent level

value - value to stringify

Throws:

java.io.IOException - failure while writing

writeBasicValueOn

protected static void writeBasicValueOn(java.io.Writer ps,
                                        int indent,
                                        java.lang.Object value)
                                 throws java.io.IOException

Writes a given value on a writer. Recognizes descriptions, strings and vectors of basic values and turns them into string representation. Default is to turn into string using normal toString() call

Parameters:

ps - writer to write on

indent - indent level

value - value to stringify

Throws:

java.io.IOException - failure while writing

getBasicValueFor

public static java.lang.String getBasicValueFor(java.lang.Object obj)
                                         throws java.io.IOException

Gets a given value in its String form. Recognizes descriptions, strings and vectors of basic values and turns them into string representation. Default is to turn into string using normal toString() call

Parameters:

obj - Object to be given in String form

Returns:

String

Throws:

java.io.IOException - failure while writing

tabPad

protected static void tabPad(java.io.Writer ps,
                             int amount)
                      throws java.io.IOException

Internal method to pad out a writer.

Parameters:

ps - writer to tab to

amount - amount to tab

Throws:

java.io.IOException - failure while writing