Examples of mf.org.apache.xerces.util.SymbolTable

mf.org.apache.xerces.util.SymbolTable
This class is a symbol table implementation that guarantees that strings used as identifiers are unique references. Multiple calls to addSymbol will always return the same string reference.
The symbol table performs the same task as String.intern() with the following differences:
- A new string object does not need to be created in order to retrieve a unique reference. Symbols can be added by using a series of characters in a character array.
- Users of the symbol table can provide their own symbol hashing implementation. For example, a simple string hashing algorithm may fail to produce a balanced set of hashcodes for symbols that are mostly unique. Strings with similar leading characters are especially prone to this poor hashing behavior.
An instance of SymbolTable has two parameters that affect its performance: initial capacity and load factor. The capacity is the number of buckets in the SymbolTable, and the initial capacity is simply the capacity at the time the SymbolTable is created. Note that the SymbolTable is open: in the case of a "hash collision", a single bucket stores multiple entries, which must be searched sequentially. The load factor is a measure of how full the SymbolTable is allowed to get before its capacity is automatically increased. When the number of entries in the SymbolTable exceeds the product of the load factor and the current capacity, the capacity is increased by calling the rehash method.
Generally, the default load factor (.75) offers a good tradeoff between time and space costs. Higher values decrease the space overhead but increase the time cost to look up an entry (which is reflected in most SymbolTable operations, including addSymbol and containsSymbol).
The initial capacity controls a tradeoff between wasted space and the need for rehash operations, which are time-consuming. No rehash operations will ever occur if the initial capacity is greater than the maximum number of entries the Hashtable will contain divided by its load factor. However, setting the initial capacity too high can waste space.
If many entries are to be made into a SymbolTable, creating it with a sufficiently large capacity may allow the entries to be inserted more efficiently than letting it perform automatic rehashing as needed to grow the table.
@see SymbolHash @author Andy Clark @author John Kim, IBM @version $Id: SymbolTable.java 985518 2010-08-14 16:02:52Z mrglavas $


        for (int i = 0; i < argv.length; i++) {
            final String expression = argv[i];
            System.out.println("# XPath expression: \""+expression+'"');
            try {
                SymbolTable symbolTable = new SymbolTable();
                XPath xpath = new XPath(expression, symbolTable, null);
                System.out.println("expanded xpath: \""+xpath.toString()+'"');
            }
            catch (XPathException e) {
                System.out.println("error: "+e.getMessage());

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    // Constructors
    //


    /** Default constructor. */
    public CachingParserPool() {
        this(new SymbolTable(), new XMLGrammarPoolImpl());
    } // <init>()

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    // factory methods


    /** Creates a new DOM parser. */
    public DOMParser createDOMParser() {
        SymbolTable symbolTable = fShadowSymbolTable
                                ? new ShadowedSymbolTable(fSynchronizedSymbolTable)
                                : fSynchronizedSymbolTable;
        XMLGrammarPool grammarPool = fShadowGrammarPool
                                ? new ShadowedGrammarPool(fSynchronizedGrammarPool)
                                : fSynchronizedGrammarPool;

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        return new DOMParser(symbolTable, grammarPool);
    } // createDOMParser():DOMParser


    /** Creates a new SAX parser. */
    public SAXParser createSAXParser() {
        SymbolTable symbolTable = fShadowSymbolTable
                                ? new ShadowedSymbolTable(fSynchronizedSymbolTable)
                                : fSynchronizedSymbolTable;
        XMLGrammarPool grammarPool = fShadowGrammarPool
                                ? new ShadowedGrammarPool(fSynchronizedGrammarPool)
                                : fSynchronizedGrammarPool;

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    // Constructors
    //


    /** Deny default construction; we need a SymtolTable! */
    public XMLDTDLoader() {
        this(new SymbolTable());
    } // <init>()

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    public void setNamespaces (boolean namespaces){
        fNamespaces = namespaces;
        if (fNSBinder == null) {
            fNSBinder = new NamespaceSupport();
            fLocalNSBinder = new NamespaceSupport();
            fSymbolTable = new SymbolTable();
        }
    }

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            fFixupLanguage = true;
        }
        
        // Get symbol table.
        try {
            SymbolTable value =
                (SymbolTable)componentManager.getProperty(SYMBOL_TABLE);
            if (value != null) {
                fSymbolTable = value;
                if (fChildConfig != null) {
                    fChildConfig.setProperty(SYMBOL_TABLE, value);
                }
            }
        }
        catch (XMLConfigurationException e) {
            fSymbolTable = null;
        }


        // Get error reporter.
        try {
            XMLErrorReporter value =
                (XMLErrorReporter)componentManager.getProperty(ERROR_REPORTER);
            if (value != null) {
                setErrorReporter(value);
                if (fChildConfig != null) {
                    fChildConfig.setProperty(ERROR_REPORTER, value);
                }
            }
        }
        catch (XMLConfigurationException e) {
            fErrorReporter = null;
        }


        // Get entity resolver.
        try {
            XMLEntityResolver value =
                (XMLEntityResolver)componentManager.getProperty(
                    ENTITY_RESOLVER);


            if (value != null) {
                fEntityResolver = value;
                if (fChildConfig != null) {
                    fChildConfig.setProperty(ENTITY_RESOLVER, value);
                }
            }
        }
        catch (XMLConfigurationException e) {
            fEntityResolver = null;
        }


        // Get security manager.
        try {
            SecurityManager value =
                (SecurityManager)componentManager.getProperty(
                    SECURITY_MANAGER);


            if (value != null) {
                fSecurityManager = value;
                if (fChildConfig != null) {
                    fChildConfig.setProperty(SECURITY_MANAGER, value);
                }
            }
        }
        catch (XMLConfigurationException e) {
            fSecurityManager = null;
        }
        
        // Get buffer size.
        try {
            Integer value =
                (Integer)componentManager.getProperty(
                    BUFFER_SIZE);


            if (value != null && value.intValue() > 0) {
                fBufferSize = value.intValue();
                if (fChildConfig != null) {
                    fChildConfig.setProperty(BUFFER_SIZE, value);
                }
            }
            else {

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    // this initializes a newly-created serializer
    private void initSerializer(XMLSerializer ser) {
        ser.fNSBinder = new NamespaceSupport();
        ser.fLocalNSBinder = new NamespaceSupport();
        ser.fSymbolTable = new SymbolTable();  
    }

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Related Classes of mf.org.apache.xerces.util.SymbolTable

mf.org.apache.xerces.dom.DOMConfigurationImpl

mf.org.apache.xerces.impl.dtd.XMLDTDLoader

mf.org.apache.xerces.impl.xpath.XPath

mf.org.apache.xerces.impl.xs.XMLSchemaLoader

mf.org.apache.xerces.impl.xs.XMLSchemaValidator

mf.org.apache.xerces.jaxp.validation.XMLSchemaValidatorComponentManager

mf.org.apache.xerces.parsers.BasicParserConfiguration

mf.org.apache.xerces.parsers.CachingParserPool

mf.org.apache.xerces.parsers.XML11Configuration

mf.org.apache.xerces.parsers.XML11DTDConfiguration

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