com.yahoo.search.query.context

Class QueryContext

java.lang.Object

com.yahoo.search.query.context.QueryContext

All Implemented Interfaces:

Cloneable

public class QueryContext
extends Object
implements Cloneable

A proxy to the Execution.trace() which exists for legacy reasons. Calls to this is forwarded to owningQuery.getModel().getExecution().trace().

Author:

Steinar Knutsen, bratseth

Field Summary

Fields

Modifier and Type	Field and Description
static String	ID
private Query	owner

Constructor Summary

Constructors

Constructor and Description
QueryContext(int ignored, Query owner)

Method Summary

Modifier and Type	Method and Description
QueryContext	clone()
QueryContext	cloneFor(Query cloneOwner)
Object	getProperty(String name) Returns a property set anywhere in this context.
com.yahoo.processing.execution.Execution.Trace	getTrace() Returns the execution trace this delegates to
void	logValue(String key, Object value) Adds a key-value which will be logged to the access log for this query (by doing toString() on the value Multiple values may be set to the same key.
Iterator<com.yahoo.processing.execution.Execution.Trace.LogValue>	logValueIterator() Returns the values to be written to the access log for this
boolean	render(Writer writer)
void	setProperty(String name, Object value) Adds a property key-value to this context.
String	toString() Returns a short string description of this (includes the first few messages only, and no newlines)
void	trace(String message, int traceLevel) Adds a context message to this context

Methods inherited from class java.lang.Object

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

Field Detail

ID

public static final String ID

See Also:

Constant Field Values

owner

private Query owner

Constructor Detail

QueryContext

public QueryContext(int ignored,
                    Query owner)

Method Detail

trace

public void trace(String message,
                  int traceLevel)

Adds a context message to this context

logValue

public void logValue(String key,
                     Object value)

Adds a key-value which will be logged to the access log for this query (by doing toString() on the value Multiple values may be set to the same key. A value cannot be removed once set.

logValueIterator

public Iterator<com.yahoo.processing.execution.Execution.Trace.LogValue> logValueIterator()

Returns the values to be written to the access log for this

setProperty

public void setProperty(String name,
                        Object value)

Adds a property key-value to this context. If the same name is set multiple times, the behavior is thus:

• Within a single context (thread/query clone), the last value set is used
• Across multiple traces, the last value from the last deepest nested thread/clone is used. In the case of multiple threads writing the value concurrently to their clone, it is of course undefined which one will be used.

Parameters:

name - the name of the property

value - the value of the property, or null to set this property to null

getProperty

public Object getProperty(String name)

Returns a property set anywhere in this context. Note that even though this call is itself "thread robust", the object values returned may in some scenarios not be written behind a synchronization barrier, so when accessing objects which are not inherently thread safe, synchronization should be considered.

Note that this method have a time complexity which is proportional to the number of cloned/created queries times the average number of properties in each.

toString

public String toString()

Returns a short string description of this (includes the first few messages only, and no newlines)

Overrides:

toString in class Object

render

public boolean render(Writer writer)
               throws IOException

Throws:

IOException

cloneFor

public QueryContext cloneFor(Query cloneOwner)

getTrace

public com.yahoo.processing.execution.Execution.Trace getTrace()

Returns the execution trace this delegates to

clone

public QueryContext clone()

Overrides:

clone in class Object