java.lang.Object | |
↳ | org.apache.xerces.parsers.CachingParserPool |
A parser pool that enables caching of grammars. The caching parser pool is constructed with a specific symbol table and grammar pool that has already been populated with the grammars used by the application.
Once the caching parser pool is constructed, specific parser instances are created by calling the appropriate factory method on the parser pool.
Note: There is a performance penalty for using a caching parser pool due to thread safety. Access to the symbol table and grammar pool must be synchronized to ensure the safe operation of the symbol table and grammar pool.
Note: If performance is critical, then another mechanism needs to be used instead of the caching parser pool. One approach would be to create parser instances that do not share these structures. Instead, each instance would get its own copy to use while parsing. This avoids the synchronization overhead at the expense of more memory and the time required to copy the structures for each new parser instance. And even when a parser instance is re-used, there is a potential for a memory leak due to new symbols being added to the symbol table over time. In other words, always take caution to make sure that your application is thread-safe and avoids leaking memory.
Nested Classes | |||||||||||
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CachingParserPool.ShadowedGrammarPool | Shadowed grammar pool. | ||||||||||
CachingParserPool.SynchronizedGrammarPool | Synchronized grammar pool. |
Constants | |||||||||||
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boolean | DEFAULT_SHADOW_GRAMMAR_POOL | Default shadow grammar pool (false). | |||||||||
boolean | DEFAULT_SHADOW_SYMBOL_TABLE | Default shadow symbol table (false). |
Fields | |||||||||||
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fShadowGrammarPool | Shadow the grammar pool for new parser instances. | ||||||||||
fShadowSymbolTable | Shadow the symbol table for new parser instances. | ||||||||||
fSynchronizedGrammarPool | Grammar pool. | ||||||||||
fSynchronizedSymbolTable | Symbol table. |
Public Constructors | |||||||||||
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Default constructor.
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Constructs a caching parser pool with the specified symbol table
and grammar pool.
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Public Methods | |||||||||||
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Creates a new DOM parser.
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Creates a new SAX parser.
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Returns the symbol table.
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Returns the grammar pool.
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Sets whether new parser instance receive shadow copies of the
main symbol table.
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Inherited Methods | |||||||||||
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From class
java.lang.Object
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Default shadow grammar pool (false).
Default shadow symbol table (false).
Shadow the grammar pool for new parser instances. If true, new parser instances use shadow copies of the main grammar pool and are not allowed to add new grammars to the main grammar pool. New grammars are added to the shadow grammar pool and are local to the parser instance.
Shadow the symbol table for new parser instances. If true, new parser instances use shadow copies of the main symbol table and are not allowed to add new symbols to the main symbol table. New symbols are added to the shadow symbol table and are local to the parser instance.
Grammar pool. The grammar pool that the caching parser pool is constructed with is automatically wrapped in a synchronized version for thread-safety.
Symbol table. The symbol table that the caching parser pool is constructed with is automatically wrapped in a synchronized version for thread-safety.
Default constructor.
Constructs a caching parser pool with the specified symbol table and grammar pool.
symbolTable | The symbol table. |
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grammarPool | The grammar pool. |
Sets whether new parser instance receive shadow copies of the main symbol table.
shadow | If true, new parser instances use shadow copies of the main symbol table and are not allowed to add new symbols to the main symbol table. New symbols are added to the shadow symbol table and are local to the parser instance. If false, new parser instances are allowed to add new symbols to the main symbol table. |
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