Package org.apache.solr.response

Class ResponseWritersRegistry

java.lang.Object

org.apache.solr.response.ResponseWritersRegistry

public class ResponseWritersRegistry
extends Object

Essential response writers always available regardless of core configuration.

Used by node/container-level requests that have no associated SolrCore.

For the full set of response writers see SolrCore's response writer registry.

Method Summary

Modifier and Type	Method	Description
static Map<String,QueryResponseWriter>	getAllWriters()	Gets all built-in response writers.
static QueryResponseWriter	getWriter(String writerName)	Gets a built-in response writer.
static QueryResponseWriter	getWriter(String writerName, SolrCore core)	Gets a response writer, trying the core's registry first, then falling back to built-in writers.
static boolean	hasWriter(String writerName)	Checks if a writer with the given name exists in the built-in writers.

Methods inherited from class java.lang.Object

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

Method Details

getWriter

public static QueryResponseWriter getWriter(String writerName)

Gets a built-in response writer.

Built-in writers are always available and provide essential formats needed by admin APIs and core functionality. They do not depend on core configuration or ImplicitPlugins.json settings.

If the requested writer is not available, returns the JSON writer as a fallback. This ensures requests always get a valid response format.

Parameters:

writerName - the writer name (e.g., "json", "xml", "javabin"), or null for default

Returns:

the response writer, never null (returns JSON if not found)

getWriter

public static QueryResponseWriter getWriter(String writerName,
 SolrCore core)

Gets a response writer, trying the core's registry first, then falling back to built-in writers. This is the unified entry point for all writer resolution.

Resolution order:

1. If core is provided, check core's writer registry
2. If not found in core (or no core), check built-in writers
3. If writer name is explicitly specified but not found anywhere, throw exception
4. If writer name is null/empty, return default (JSON)

Parameters:

writerName - the writer name (e.g., "json", "xml", "javabin"), or null for default

core - the SolrCore to check first, or null for node-level requests

Returns:

the response writer, never null

Throws:

org.apache.solr.common.SolrException - if an explicitly requested writer type is not found

hasWriter

public static boolean hasWriter(String writerName)

Checks if a writer with the given name exists in the built-in writers.

Parameters:

writerName - the writer name to check

Returns:

true if the writer exists, false otherwise

getAllWriters

public static Map<String,QueryResponseWriter> getAllWriters()

Gets all built-in response writers.

Returns:

immutable map of all built-in writers