number.java

java1.6众多例子参考

/*
 * Copyright 2001-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: Number.java,v 1.2.4.1 2005/09/21 09:40:51 pvedula Exp $
 */

package com.sun.org.apache.xalan.internal.xsltc.compiler;

import java.util.ArrayList;

import com.sun.org.apache.bcel.internal.classfile.Field;
import com.sun.org.apache.bcel.internal.generic.ALOAD;
import com.sun.org.apache.bcel.internal.generic.ASTORE;
import com.sun.org.apache.bcel.internal.generic.BranchHandle;
import com.sun.org.apache.bcel.internal.generic.CHECKCAST;
import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
import com.sun.org.apache.bcel.internal.generic.GETFIELD;
import com.sun.org.apache.bcel.internal.generic.GOTO;
import com.sun.org.apache.bcel.internal.generic.IFNONNULL;
import com.sun.org.apache.bcel.internal.generic.INVOKESPECIAL;
import com.sun.org.apache.bcel.internal.generic.INVOKESTATIC;
import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
import com.sun.org.apache.bcel.internal.generic.InstructionList;
import com.sun.org.apache.bcel.internal.generic.D2I;
import com.sun.org.apache.bcel.internal.generic.LocalVariableGen;
import com.sun.org.apache.bcel.internal.generic.NEW;
import com.sun.org.apache.bcel.internal.generic.PUSH;
import com.sun.org.apache.bcel.internal.generic.PUTFIELD;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MatchGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.NodeCounterGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.RealType;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util;

/**
 * @author Jacek Ambroziak
 * @author Santiago Pericas-Geertsen
 */
final class Number extends Instruction implements Closure {
    private static final int LEVEL_SINGLE   = 0;
    private static final int LEVEL_MULTIPLE = 1;
    private static final int LEVEL_ANY      = 2;

    static final private String[] ClassNames = { 
	"com.sun.org.apache.xalan.internal.xsltc.dom.SingleNodeCounter",	  // LEVEL_SINGLE
	"com.sun.org.apache.xalan.internal.xsltc.dom.MultipleNodeCounter", // LEVEL_MULTIPLE
	"com.sun.org.apache.xalan.internal.xsltc.dom.AnyNodeCounter"	  // LEVEL_ANY
    };

    static final private String[] FieldNames = { 
	"___single_node_counter",		   // LEVEL_SINGLE
	"___multiple_node_counter",		   // LEVEL_MULTIPLE
	"___any_node_counter"			   // LEVEL_ANY
    };

    private Pattern _from = null;
    private Pattern _count = null;
    private Expression _value = null;

    private AttributeValueTemplate _lang = null;
    private AttributeValueTemplate _format = null;
    private AttributeValueTemplate _letterValue = null;
    private AttributeValueTemplate _groupingSeparator = null;
    private AttributeValueTemplate _groupingSize = null;

    private int _level = LEVEL_SINGLE;
    private boolean _formatNeeded = false;

    private String _className = null;
    private ArrayList _closureVars = null;

     // -- Begin Closure interface --------------------

    /**
     * Returns true if this closure is compiled in an inner class (i.e.
     * if this is a real closure).
     */
    public boolean inInnerClass() {
	return (_className != null);
    }

    /**
     * Returns a reference to its parent closure or null if outermost.
     */
    public Closure getParentClosure() {
	return null;
    }

    /**
     * Returns the name of the auxiliary class or null if this predicate 
     * is compiled inside the Translet.
     */
    public String getInnerClassName() {
	return _className;
    }

    /**
     * Add new variable to the closure.
     */
    public void addVariable(VariableRefBase variableRef) {
	if (_closureVars == null) {
	    _closureVars = new ArrayList();
	}

	// Only one reference per variable
	if (!_closureVars.contains(variableRef)) {
	    _closureVars.add(variableRef);
	}
    }

    // -- End Closure interface ----------------------

   public void parseContents(Parser parser) {
	final int count = _attributes.getLength();

	for (int i = 0; i < count; i++) {
	    final String name = _attributes.getQName(i);
	    final String value = _attributes.getValue(i);

	    if (name.equals("value")) {
		_value = parser.parseExpression(this, name, null);
	    }
	    else if (name.equals("count")) {
		_count = parser.parsePattern(this, name, null);
	    }
	    else if (name.equals("from")) {
		_from = parser.parsePattern(this, name, null);
	    }
	    else if (name.equals("level")) {
		if (value.equals("single")) {
		    _level = LEVEL_SINGLE;
		}
		else if (value.equals("multiple")) {
		    _level = LEVEL_MULTIPLE;
		}
		else if (value.equals("any")) {
		    _level = LEVEL_ANY;
		}
	    }
	    else if (name.equals("format")) {
		_format = new AttributeValueTemplate(value, parser, this);
		_formatNeeded = true;
	    }
	    else if (name.equals("lang")) {
		_lang = new AttributeValueTemplate(value, parser, this);
		_formatNeeded = true;
	    }
	    else if (name.equals("letter-value")) {
		_letterValue = new AttributeValueTemplate(value, parser, this);
		_formatNeeded = true;
	    }
	    else if (name.equals("grouping-separator")) {
		_groupingSeparator = new AttributeValueTemplate(value, parser, this);
		_formatNeeded = true;
	    }
	    else if (name.equals("grouping-size")) {
		_groupingSize = new AttributeValueTemplate(value, parser, this);
		_formatNeeded = true;
	    }
	}
    }

    public Type typeCheck(SymbolTable stable) throws TypeCheckError {
	if (_value != null) {
	    Type tvalue = _value.typeCheck(stable);
	    if (tvalue instanceof RealType == false) {
		_value = new CastExpr(_value, Type.Real);
	    }
	}
	if (_count != null) {
	    _count.typeCheck(stable);
	}
	if (_from != null) {
	    _from.typeCheck(stable);
	}
	if (_format != null) {
	    _format.typeCheck(stable);
	}
	if (_lang != null) {
	    _lang.typeCheck(stable);
	}
	if (_letterValue != null) {
	    _letterValue.typeCheck(stable);
	}
	if (_groupingSeparator != null) {
	    _groupingSeparator.typeCheck(stable);
	}
	if (_groupingSize != null) {
	    _groupingSize.typeCheck(stable);
	}
	return Type.Void;
    }

    /**
     * True if the has specified a value for this instance of number.
     */
    public boolean hasValue() {
	return _value != null;
    }

    /**
     * Returns <tt>true</tt> if this instance of number has neither
     * a from nor a count pattern.
     */
    public boolean isDefault() {
	return _from == null && _count == null;
    }

    private void compileDefault(ClassGenerator classGen,
			        MethodGenerator methodGen) {
	int index;
	ConstantPoolGen cpg = classGen.getConstantPool();
	InstructionList il = methodGen.getInstructionList();

	int[] fieldIndexes = getXSLTC().getNumberFieldIndexes();

	if (fieldIndexes[_level] == -1) {
	    Field defaultNode = new Field(ACC_PRIVATE, 
					  cpg.addUtf8(FieldNames[_level]),
					  cpg.addUtf8(NODE_COUNTER_SIG),
					  null, 
					  cpg.getConstantPool());

	    // Add a new private field to this class
	    classGen.addField(defaultNode);

	    // Get a reference to the newly added field
	    fieldIndexes[_level] = cpg.addFieldref(classGen.getClassName(), 
						   FieldNames[_level],
						   NODE_COUNTER_SIG);
	}

	// Check if field is initialized (runtime)
	il.append(classGen.loadTranslet());
	il.append(new GETFIELD(fieldIndexes[_level]));
	final BranchHandle ifBlock1 = il.append(new IFNONNULL(null));

	// Create an instance of DefaultNodeCounter
	index = cpg.addMethodref(ClassNames[_level],
				 "getDefaultNodeCounter", 
				 "(" + TRANSLET_INTF_SIG
				 + DOM_INTF_SIG
				 + NODE_ITERATOR_SIG 
				 + ")" + NODE_COUNTER_SIG);
	il.append(classGen.loadTranslet());
	il.append(methodGen.loadDOM());
	il.append(methodGen.loadIterator());
	il.append(new INVOKESTATIC(index));
	il.append(DUP);

	// Store the node counter in the field
	il.append(classGen.loadTranslet());
	il.append(SWAP);
	il.append(new PUTFIELD(fieldIndexes[_level]));
	final BranchHandle ifBlock2 = il.append(new GOTO(null));

	// Backpatch conditionals
	ifBlock1.setTarget(il.append(classGen.loadTranslet()));
	il.append(new GETFIELD(fieldIndexes[_level]));
	
	ifBlock2.setTarget(il.append(NOP));
    }

    /**
     * Compiles a constructor for the class <tt>_className</tt> that
     * inherits from {Any,Single,Multiple}NodeCounter. This constructor
     * simply calls the same constructor in the super class.
     */
    private void compileConstructor(ClassGenerator classGen) {
	MethodGenerator cons;
	final InstructionList il = new InstructionList();
	final ConstantPoolGen cpg = classGen.getConstantPool();

	cons = new MethodGenerator(ACC_PUBLIC,
				   com.sun.org.apache.bcel.internal.generic.Type.VOID, 
				   new com.sun.org.apache.bcel.internal.generic.Type[] {
				       Util.getJCRefType(TRANSLET_INTF_SIG),
				       Util.getJCRefType(DOM_INTF_SIG),
				       Util.getJCRefType(NODE_ITERATOR_SIG)
				   },
				   new String[] {
				       "dom",
				       "translet",
				       "iterator"
				   },
				   "<init>", _className, il, cpg);