Package org.apache.tika.serialization

Class ConfigDeserializer

java.lang.Object

org.apache.tika.serialization.ConfigDeserializer

public class ConfigDeserializer
extends Object

Helper utility for SelfConfiguring components to deserialize their configuration from ParseContext at run time.

Note for Parser Developers: Instead of calling this class directly, use ParseContextConfig which provides the same functionality but with better error handling. ParseContextConfig will throw a clear exception if tika-serialization is not on the classpath.

This allows parsers to retrieve their configuration using the same friendly names as in tika-config.json (e.g., "pdf-parser", "html-parser") from per-request configurations sent via FetchEmitTuple or other serialization mechanisms.

The helper automatically merges user configuration with parser defaults, eliminating the need for config-specific cloneAndUpdate methods.

Example usage in a parser:

 // Recommended: Use ParseContextConfig wrapper (in tika-core)
 PDFParserConfig localConfig = ParseContextConfig.getConfig(
     context, "pdf-parser", PDFParserConfig.class, defaultConfig);
 

See Also:

• ParseContextConfig

Constructor Summary

Constructors

Constructor	Description
ConfigDeserializer()

Method Summary

Modifier and Type	Method	Description
static <T> T	getConfig(ParseContext context, String configKey, Class<T> configClass)	Retrieves and deserializes a configuration from ParseContext.
static <T> T	getConfig(ParseContext context, String configKey, Class<T> configClass, T defaultConfig)	Retrieves and deserializes a configuration from ParseContext.
static boolean	hasConfig(ParseContext context, String configKey)	Checks if a configuration exists in the ParseContext.

Methods inherited from class java.lang.Object

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

Constructor Details

ConfigDeserializer

public ConfigDeserializer()

Method Details

getConfig

public static <T> T getConfig(ParseContext context,
 String configKey,
 Class<T> configClass,
 T defaultConfig)
                       throws IOException

Retrieves and deserializes a configuration from ParseContext.

Resolution order:

1. Check resolved configs cache (already deserialized)
2. Check JSON configs (deserialize, merge with default, cache)
3. Return default config if nothing found

The resolved config is cached in ParseContext's resolvedConfigs map and also set in the main context map so components can find it via parseContext.get(configClass).

Type Parameters:

T - the configuration type

Parameters:

context - the parse context

configKey - the configuration key (e.g., "pdf-parser", "handler-config")

configClass - the configuration class to deserialize into

defaultConfig - optional default config to merge with user config (can be null)

Returns:

the merged configuration, the default config if no user config found, or null if neither exists

Throws:

IOException - if deserialization fails

getConfig

public static <T> T getConfig(ParseContext context,
 String configKey,
 Class<T> configClass)
                       throws IOException

Retrieves and deserializes a configuration from ParseContext. This version does not merge with any default config.

Type Parameters:

T - the configuration type

Parameters:

context - the parse context

configKey - the configuration key (e.g., "pdf-parser", "handler-config")

configClass - the configuration class to deserialize into

Returns:

the deserialized configuration, or null if not found

Throws:

IOException - if deserialization fails

hasConfig

public static boolean hasConfig(ParseContext context,
 String configKey)

Checks if a configuration exists in the ParseContext.

Parameters:

context - the parse context

configKey - the configuration key to check

Returns:

true if the configuration exists (either as JSON or already resolved)