org.apache.xalan.xsltc.compiler

Class Pattern

java.lang.Object

org.apache.xalan.xsltc.compiler.SyntaxTreeNode

org.apache.xalan.xsltc.compiler.Pattern

All Implemented Interfaces:

org.apache.bcel.generic.InstructionConstants, Constants

Direct Known Subclasses:

LocationPathPattern

public abstract class Pattern
extends SyntaxTreeNode

Author:

Jacek Ambroziak, Santiago Pericas-Geertsen

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.bcel.generic.InstructionConstants

org.apache.bcel.generic.InstructionConstants.Clinit

Field Summary

Fields

Modifier and Type	Field and Description
protected FlowList	_falseList Instruction handles that comprise the false list.
protected FlowList	_trueList Instruction handles that comprise the true list.
protected Type	_type The type of this expression.

Fields inherited from class org.apache.xalan.xsltc.compiler.SyntaxTreeNode

_attributes, _parent, _qname, IndentIncrement, UNKNOWN_STYLESHEET_NODE_ID

Fields inherited from interface org.apache.xalan.xsltc.compiler.Constants

ABSOLUTE_ITERATOR, ACC_FINAL, ACC_PRIVATE, ACC_PROTECTED, ACC_PUBLIC, ACC_STATIC, ACC_SUPER, ADD_ATTRIBUTE, ADD_ATTRIBUTE_SIG, ADD_ITERATOR, ADD_ITERATOR_SIG, ADD_PARAMETER, ADD_PARAMETER_SIG, APPLY_TEMPLATES, ATTR_SET_SIG, ATTRIBUTE_LIST_FIELD, ATTRIBUTE_LIST_IMPL_CLASS, ATTRIBUTE_LIST_IMPL_SIG, ATTRIBUTES_SIG, BASIS_LIBRARY_CLASS, BOOLEAN_CLASS, BOOLEAN_VALUE, BOOLEAN_VALUE_SIG, CACHED_NODE_LIST_ITERATOR_CLASS, CHARACTERS, CHARACTERS_SIG, CHARACTERSW, CHARACTERSW_SIG, CLEAR_ATTRIBUTES, CLEAR_ATTRIBUTES_SIG, COLLATOR_CLASS, COLLATOR_SIG, COMPILER_PACKAGE, CURRENT_NODE_LIST_FILTER, CURRENT_NODE_LIST_FILTER_SIG, CURRENT_NODE_LIST_ITERATOR, CURRENT_NODE_LIST_ITERATOR_SIG, DEFAULT_NODE_COUNTER, DEFAULT_NODE_COUNTER_SIG, DOCUMENT_PNAME, DOM_ADAPTER_CLASS, DOM_ADAPTER_SIG, DOM_FIELD, DOM_IMPL, DOM_IMPL_CLASS, DOM_IMPL_SIG, DOM_INTF, DOM_INTF_SIG, DOM_PNAME, DOUBLE_CLASS, DOUBLE_SIG, DOUBLE_VALUE, DOUBLE_VALUE_SIG, DUP_FILTERED_ITERATOR, EMPTYATTR_FIELD, EMPTYSTRING, ERROR, EXPAND_STYLESHEET_QNAME_REF, EXPAND_STYLESHEET_QNAME_SIG, FALLBACK_CLASS, FATAL, FILTER_INTERFACE, FILTER_INTERFACE_SIG, FILTER_ITERATOR, FILTER_STEP_ITERATOR, FORMAT_SYMBOLS_FIELD, GET_ATTRIBUTE_VALUE, GET_ATTRIBUTE_VALUE_SIG, GET_CHILDREN, GET_CHILDREN_SIG, GET_ELEMENT_VALUE, GET_ELEMENT_VALUE_SIG, GET_ITERATOR_SIG, GET_NODE_NAME, GET_NODE_NAME_SIG, GET_NODE_TYPE, GET_NODE_TYPE_SIG, GET_NODE_VALUE, GET_NODE_VALUE_ITERATOR, GET_NODE_VALUE_ITERATOR_SIG, GET_NODE_VALUE_SIG, GET_PARAMETER, GET_PARAMETER_SIG, GET_PARENT, GET_PARENT_SIG, GET_TYPED_CHILDREN, GET_TYPED_CHILDREN_SIG, GET_UNPARSED_ENTITY_URI, GET_UNPARSED_ENTITY_URI_SIG, HAS_ATTRIBUTE, HAS_ATTRIBUTE_SIG, HASIDCALL_INDEX, HASIDCALL_INDEX_SIG, INT_VALUE, INT_VALUE_SIG, INTEGER_CLASS, INTEGER_SIG, INTERNAL, INVOKE_METHOD, ITERATOR_FIELD_SIG, ITERATOR_PNAME, KEY_INDEX_CLASS, KEY_INDEX_ITERATOR_SIG, KEY_INDEX_SIG, LAST_INDEX, LOAD_DOCUMENT_CLASS, LOCALE_CLASS, LOCALE_SIG, LOOKUP_STYLESHEET_QNAME_NS_REF, LOOKUP_STYLESHEET_QNAME_NS_SIG, MAKE_NODE, MAKE_NODE_LIST, MAKE_NODE_LIST_SIG, MAKE_NODE_LIST_SIG2, MAKE_NODE_SIG, MAKE_NODE_SIG2, MATCHING_ITERATOR, MATH_CLASS, MULTI_DOM_CLASS, MULTI_DOM_SIG, NAMES_INDEX, NAMES_INDEX_SIG, NAMESPACE_FEATURE, NAMESPACE_INDEX, NAMESPACE_INDEX_SIG, NEXT, NEXT_SIG, NEXTID, NODE, NODE_COUNTER, NODE_COUNTER_SIG, NODE_FIELD, NODE_FIELD_SIG, NODE_ITERATOR, NODE_ITERATOR_BASE, NODE_ITERATOR_SIG, NODE_PNAME, NODE_SIG, NODE_SORT_FACTORY, NODE_SORT_FACTORY_SIG, NODE_SORT_RECORD, NODE_SORT_RECORD_SIG, NS_ANCESTORS_INDEX_SIG, NTH_ITERATOR_CLASS, OBJECT_CLASS, OBJECT_SIG, ORDER_ITERATOR, ORDER_ITERATOR_SIG, OUTPUT_BASE, OUTPUT_HANDLER, OUTPUT_HANDLER_SIG, POP_PARAM_FRAME, POP_PARAM_FRAME_SIG, POSITION_INDEX, PREFIX_URIS_ARRAY_SIG, PREFIX_URIS_IDX_SIG, PUSH_PARAM_FRAME, PUSH_PARAM_FRAME_SIG, REDIRECT_URI, RESET, RESET_SIG, RTF_INITIAL_SIZE, RUNTIME_NODE_CLASS, RUNTIME_PACKAGE, SAX_IMPL, SAX_IMPL_CLASS, SAX_IMPL_SIG, SET_START_NODE, SET_START_NODE_SIG, SINGLETON_ITERATOR, SORT_ITERATOR, SORT_ITERATOR_SIG, STATIC_CHAR_DATA_FIELD, STATIC_CHAR_DATA_FIELD_SIG, STATIC_NAMES_ARRAY_FIELD, STATIC_NAMESPACE_ARRAY_FIELD, STATIC_NS_ANCESTORS_ARRAY_FIELD, STATIC_PREFIX_URIS_ARRAY_FIELD, STATIC_PREFIX_URIS_IDX_ARRAY_FIELD, STATIC_TYPES_ARRAY_FIELD, STATIC_URIS_ARRAY_FIELD, STEP_ITERATOR_CLASS, STREAM_XML_OUTPUT, STRING, STRING_BUFFER_CLASS, STRING_BUFFER_SIG, STRING_CLASS, STRING_SIG, STRING_TO_INT, STRING_TO_INT_SIG, STRING_TO_REAL, STRING_TO_REAL_SIG, STRING_VALUE_HANDLER, STRING_VALUE_HANDLER_SIG, STRING_WRITER, STRIP_SPACE, STRIP_SPACE_INTF, STRIP_SPACE_PARAMS, STRIP_SPACE_SIG, TRANSLET_CLASS, TRANSLET_FIELD, TRANSLET_FIELD_SIG, TRANSLET_INTF, TRANSLET_INTF_SIG, TRANSLET_OUTPUT_BASE, TRANSLET_OUTPUT_INTERFACE, TRANSLET_OUTPUT_PNAME, TRANSLET_OUTPUT_SIG, TRANSLET_PNAME, TRANSLET_SIG, TRANSLET_URI, TRANSLET_VERSION_INDEX, TRANSLET_VERSION_INDEX_SIG, TYPES_INDEX, TYPES_INDEX_SIG, UNION_ITERATOR_CLASS, UNION_ITERATOR_SIG, UNSUPPORTED, URIS_INDEX, URIS_INDEX_SIG, WARNING, WRITER_SIG, XHTML_URI, XMLNS_PREFIX, XMLNS_STRING, XMLNS_URI, XSLT_PACKAGE, XSLT_URI

Fields inherited from interface org.apache.bcel.generic.InstructionConstants

AALOAD, AASTORE, ACONST_NULL, ALOAD_0, ALOAD_1, ALOAD_2, ARETURN, ARRAYLENGTH, ASTORE_0, ASTORE_1, ASTORE_2, ATHROW, BALOAD, BASTORE, bla, CALOAD, CASTORE, D2F, D2I, D2L, DADD, DALOAD, DASTORE, DCMPG, DCMPL, DCONST_0, DCONST_1, DDIV, DMUL, DNEG, DREM, DRETURN, DSUB, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, F2D, F2I, F2L, FADD, FALOAD, FASTORE, FCMPG, FCMPL, FCONST_0, FCONST_1, FCONST_2, FDIV, FMUL, FNEG, FREM, FRETURN, FSUB, I2B, I2C, I2D, I2F, I2L, I2S, IADD, IALOAD, IAND, IASTORE, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, ICONST_5, ICONST_M1, IDIV, ILOAD_0, ILOAD_1, ILOAD_2, IMUL, INEG, INSTRUCTIONS, IOR, IREM, IRETURN, ISHL, ISHR, ISTORE_0, ISTORE_1, ISTORE_2, ISUB, IUSHR, IXOR, L2D, L2F, L2I, LADD, LALOAD, LAND, LASTORE, LCMP, LCONST_0, LCONST_1, LDIV, LMUL, LNEG, LOR, LREM, LRETURN, LSHL, LSHR, LSUB, LUSHR, LXOR, MONITORENTER, MONITOREXIT, NOP, POP, POP2, RETURN, SALOAD, SASTORE, SWAP, THIS

Constructor Summary

Constructors

Constructor and Description
Pattern()

Method Summary

Modifier and Type	Method and Description
void	backPatchFalseList(org.apache.bcel.generic.InstructionHandle ih)
void	backPatchTrueList(org.apache.bcel.generic.InstructionHandle ih)
org.apache.bcel.generic.InstructionList	compile(ClassGenerator classGen, MethodGenerator methodGen) Translate this node into a fresh instruction list.
void	desynthesize(ClassGenerator classGen, MethodGenerator methodGen)
Object	evaluateAtCompileTime() Returns an object representing the compile-time evaluation of an expression.
FlowList	getFalseList()
abstract double	getPriority() Returns the priority of this pattern (section 5.5 in the XSLT spec).
FlowList	getTrueList()
Type	getType()
boolean	hasLastCall()
boolean	hasPositionCall()
MethodType	lookupPrimop(org.apache.xalan.xsltc.compiler.SymbolTable stable, String op, MethodType ctype) Search for a primop in the symbol table that matches the method type ctype.
void	startIterator(ClassGenerator classGen, MethodGenerator methodGen) If this expression is of type node-set and it is not a variable reference, then call setStartNode() passing the context node.
void	synthesize(ClassGenerator classGen, MethodGenerator methodGen) Synthesize a boolean expression, i.e., either push a 0 or 1 onto the operand stack for the next statement to succeed.
abstract String	toString()
abstract void	translate(ClassGenerator classGen, MethodGenerator methodGen) Translate this node into JVM bytecodes.
void	translateDesynthesized(ClassGenerator classGen, MethodGenerator methodGen) Redefined by expressions of type boolean that use flow lists.
abstract Type	typeCheck(org.apache.xalan.xsltc.compiler.SymbolTable stable) Returns the type of a pattern, which is always a NodeType.

Methods inherited from class org.apache.xalan.xsltc.compiler.SyntaxTreeNode

addAttribute, addElement, addPrefixMapping, compileResultTree, contextDependent, dependentContents, display, displayContents, elementAt, elementCount, elements, getAttribute, getAttribute, getAttributes, getContents, getImportPrecedence, getLineNumber, getNodeIDForStylesheetNSLookup, getParent, getParser, getPrefixMapping, getQName, getStylesheet, getSymbolTable, getTemplate, getXSLTC, hasAttribute, hasContents, indent, isDummy, lastChild, lookupNamespace, lookupPrefix, parseChildren, parseContents, removeElement, reportError, reportWarning, setAttributes, setFirstElement, setLineNumber, setParent, setParser, setPrefixMapping, setQName, setQName, translateContents, typeCheckContents, updateScope

Methods inherited from class java.lang.Object

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

Field Detail

_type

protected Type _type

The type of this expression. It is set after calling typeCheck().

_trueList

protected FlowList _trueList

Instruction handles that comprise the true list.

_falseList

protected FlowList _falseList

Instruction handles that comprise the false list.

Constructor Detail

Pattern

public Pattern()

Method Detail

typeCheck

public abstract Type typeCheck(org.apache.xalan.xsltc.compiler.SymbolTable stable)
                        throws TypeCheckError

Returns the type of a pattern, which is always a NodeType. A NodeType has a number of subtypes defined by NodeType._type corresponding to each type of node.

Parameters:

stable - The compiler/parser's symbol table

Throws:

TypeCheckError

translate

public abstract void translate(ClassGenerator classGen,
                               MethodGenerator methodGen)

Translate this node into JVM bytecodes. Patterns are translated as boolean expressions with true/false lists. Before calling translate on a pattern, make sure that the node being matched is on top of the stack. After calling translate, make sure to backpatch both true and false lists. True lists are the default, in the sense that they always "fall through". If this is not the intended semantics (e.g., see AlternativePattern.translate(org.apache.xalan.xsltc.compiler.util.ClassGenerator, org.apache.xalan.xsltc.compiler.util.MethodGenerator)) then a GOTO must be appended to the instruction list after calling translate.

Parameters:

classGen - BCEL Java class generator

methodGen - BCEL Java method generator

getPriority

public abstract double getPriority()

Returns the priority of this pattern (section 5.5 in the XSLT spec).

getType

public Type getType()

toString

public abstract String toString()

Overrides:

toString in class Object

hasPositionCall

public boolean hasPositionCall()

hasLastCall

public boolean hasLastCall()

evaluateAtCompileTime

public Object evaluateAtCompileTime()

Returns an object representing the compile-time evaluation of an expression. We are only using this for function-available and element-available at this time.

compile

public final org.apache.bcel.generic.InstructionList compile(ClassGenerator classGen,
                                                             MethodGenerator methodGen)

Translate this node into a fresh instruction list. The original instruction list is saved and restored.

translateDesynthesized

public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)

Redefined by expressions of type boolean that use flow lists.

startIterator

public void startIterator(ClassGenerator classGen,
                          MethodGenerator methodGen)

If this expression is of type node-set and it is not a variable reference, then call setStartNode() passing the context node.

synthesize

public void synthesize(ClassGenerator classGen,
                       MethodGenerator methodGen)

Synthesize a boolean expression, i.e., either push a 0 or 1 onto the operand stack for the next statement to succeed. Returns the handle of the instruction to be backpatched.

desynthesize

public void desynthesize(ClassGenerator classGen,
                         MethodGenerator methodGen)

getFalseList

public FlowList getFalseList()

getTrueList

public FlowList getTrueList()

backPatchFalseList

public void backPatchFalseList(org.apache.bcel.generic.InstructionHandle ih)

backPatchTrueList

public void backPatchTrueList(org.apache.bcel.generic.InstructionHandle ih)

lookupPrimop

public MethodType lookupPrimop(org.apache.xalan.xsltc.compiler.SymbolTable stable,
                               String op,
                               MethodType ctype)

Search for a primop in the symbol table that matches the method type ctype. Two methods match if they have the same arity. If a primop is overloaded then the "closest match" is returned. The first entry in the vector of primops that has the right arity is considered to be the default one.