package org.drools.compiler.xml;
/*
*
*
* 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.
*/
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import org.drools.compiler.xml.rules.RestrictionConnectiveHandler;
import org.drools.core.util.ReflectiveVisitor;
import org.drools.lang.descr.AccumulateDescr;
import org.drools.lang.descr.AndDescr;
import org.drools.lang.descr.AttributeDescr;
import org.drools.lang.descr.CollectDescr;
import org.drools.lang.descr.EvalDescr;
import org.drools.lang.descr.ExistsDescr;
import org.drools.lang.descr.FieldBindingDescr;
import org.drools.lang.descr.FieldConstraintDescr;
import org.drools.lang.descr.ForallDescr;
import org.drools.lang.descr.FromDescr;
import org.drools.lang.descr.FunctionDescr;
import org.drools.lang.descr.FunctionImportDescr;
import org.drools.lang.descr.GlobalDescr;
import org.drools.lang.descr.ImportDescr;
import org.drools.lang.descr.LiteralRestrictionDescr;
import org.drools.lang.descr.NotDescr;
import org.drools.lang.descr.OrDescr;
import org.drools.lang.descr.PackageDescr;
import org.drools.lang.descr.PackageDescrDumper;
import org.drools.lang.descr.PatternDescr;
import org.drools.lang.descr.PredicateDescr;
import org.drools.lang.descr.QualifiedIdentifierRestrictionDescr;
import org.drools.lang.descr.QueryDescr;
import org.drools.lang.descr.RestrictionConnectiveDescr;
import org.drools.lang.descr.ReturnValueRestrictionDescr;
import org.drools.lang.descr.RuleDescr;
import org.drools.lang.descr.VariableRestrictionDescr;
/**
* This utility will take a AST of a rule package, and emit XML.
* This can be used in porting from DRL to XML.
* @author <a href="mailto:jayaramcs@gmail.com">Author Jayaram C S</a>
*/
public class XmlDumper extends ReflectiveVisitor
implements
PackageDescrDumper {
private StringBuilder xmlDump;
private boolean patternContext;
private final static String eol = System.getProperty( "line.separator" );
private String template;
public synchronized String dump(final PackageDescr packageDescr) {
this.xmlDump = new StringBuilder();
visitPackageDescr( packageDescr );
return this.xmlDump.toString();
}
public void visitAndDescr(final AndDescr descr) {
this.template = new String();
if ( descr.getDescrs() != Collections.EMPTY_LIST ) {
if ( !this.patternContext ) this.template = "<and-conditional-element>" + processDescrList( descr.getDescrs() ) + "</and-conditional-element>";
else this.template = "<and-constraint-connective>" + processDescrList( descr.getDescrs() ) + "</and-constraint-connective>";
}
}
public void visitAttributeDescr(final AttributeDescr attributeDescr) {
this.template = new String();
this.template = "<rule-attribute name=\"" + attributeDescr.getName() + "\" value=\"" + attributeDescr.getValue() + "\" />" + XmlDumper.eol;
}
public void visitVariableRestrictionDescr(final VariableRestrictionDescr descr) {
this.template = new String();
this.template = "<variable-restriction evaluator=\"" + replaceIllegalChars( descr.getEvaluator() ) + "\" identifier=\"" + descr.getIdentifier() + "\" />" + XmlDumper.eol;
}
public void visitPatternDescr(final PatternDescr descr) {
this.patternContext = true;
this.template = new String();
StringBuilder localString = new StringBuilder();
if ( descr.getDescrs() != Collections.EMPTY_LIST ) {
if ( descr.getIdentifier() != null ) {
localString.append( "<pattern identifier=\"" + descr.getIdentifier() + "\" object-type=\"" + descr.getObjectType() + "\" >" + XmlDumper.eol + processDescrList( descr.getDescrs() ) + XmlDumper.eol );
} else {
localString.append( "<pattern object-type=\"" + descr.getObjectType() + "\" >" + XmlDumper.eol + processDescrList( descr.getDescrs() ) + XmlDumper.eol );
}
} else {
if ( descr.getIdentifier() != null ) {
localString.append( "<pattern identifier=\"" + descr.getIdentifier() + "\" object-type=\"" + descr.getObjectType() + "\" >" + XmlDumper.eol );;
} else {
localString.append( "<pattern object-type=\"" + descr.getObjectType() + "\" >" + XmlDumper.eol );
}
}
if ( descr.getSource() != null ) {
visit( descr.getSource() );
localString.append( this.template );
}
localString.append( "</pattern>" + XmlDumper.eol );
this.template = localString.toString();
this.patternContext = false;
}
public void visitFieldConstraintDescr(final FieldConstraintDescr descr) {
if ( !descr.getRestrictions().isEmpty() ) {
this.template = "<field-constraint field-name=\"" + descr.getFieldName() + "\"> " + XmlDumper.eol + processFieldConstraint( descr.getRestrictions() ) + XmlDumper.eol + "</field-constraint>";
}
}
public void visitCollectDescr(final CollectDescr descr) {
StringBuilder tmpstr = new StringBuilder();
tmpstr.append( "<from> <collect>" );
visit( descr.getInputPattern() );
tmpstr.append( this.template );
tmpstr.append( " </collect> </from> " );
this.template = tmpstr.toString();
}
public void visitAccumulateDescr(final AccumulateDescr descr) {
String tmpstr = new String();
tmpstr += this.template + " <from> <accumulate> ";
if ( descr.isSinglePattern() ) {
visitPatternDescr( descr.getInputPattern() );
} else {
this.patternContext = false;
visit( descr.getInput() );
}
tmpstr += this.template;
if ( descr.isExternalFunction() ) tmpstr += "<external-function evaluator=\"" + descr.getFunctionIdentifier() + "\" expression=\"" + descr.getExpression() + "\"/>";
else tmpstr += "<init>" + descr.getInitCode() + "</init><action>" + descr.getActionCode() + "</action><result>" + descr.getResultCode() + "</result>";
this.template = tmpstr + " </accumulate> </from> ";
}
public void visitFromDescr(final FromDescr descr) {
String tmpstr = new String();
tmpstr += this.template + " <from> <expression> ";
tmpstr += descr.getDataSource();
this.template = tmpstr + " </expression> </from> ";
}
public void visitForallDescr(final ForallDescr descr) {
this.template = "<forall>" + processDescrList( descr.getDescrs() ) + "</forall>";
}
public void visitEvalDescr(final EvalDescr descr) {
this.template = new String();
this.template = "<eval>" + replaceIllegalChars( (String) descr.getContent() ) + "</eval>" + XmlDumper.eol;
}
public void visitExistsDescr(final ExistsDescr descr) {
this.template = new String();
if ( descr.getDescrs() != Collections.EMPTY_LIST ) {
this.template = "<exists>" + processDescrList( descr.getDescrs() ) + "</exists>";
} else {
this.template = "<exists> </exists>";
}
}
public void visitFieldBindingDescr(final FieldBindingDescr descr) {
this.template = new String();
this.template = "<field-binding field-name=\"" + descr.getFieldName() + "\" identifier=\"" + descr.getIdentifier() + "\" />" + XmlDumper.eol;
}
public void visitFunctionDescr(final FunctionDescr functionDescr) {
this.template = new String();
final String parameterTemplate = processParameters( functionDescr.getParameterNames(),
functionDescr.getParameterTypes() );
this.template = "<function return-type=\"" + functionDescr.getReturnType() + "\" name=\"" + functionDescr.getName() + "\">" + XmlDumper.eol + parameterTemplate + "<body>" + XmlDumper.eol + replaceIllegalChars( functionDescr.getText() )
+ XmlDumper.eol + "</body>" + XmlDumper.eol + "</function>" + XmlDumper.eol;
}
public void visitLiteralRestrictionDescr(final LiteralRestrictionDescr descr) {
this.template = new String();
this.template = "<literal-restriction evaluator=\"" + replaceIllegalChars( descr.getEvaluator() ) + "\" value=\"" + replaceIllegalChars( descr.getText() ) + "\" />" + XmlDumper.eol;
}
public void visitQualifiedIdentifierRestrictionDescr(final QualifiedIdentifierRestrictionDescr descr) {
this.template = new String();
this.template = "<qualified-identifier-restriction evaluator=\"" + replaceIllegalChars( descr.getEvaluator() ) + "\">" + replaceIllegalChars( descr.getText() ) + " </qualified-identifier-restriction>" + XmlDumper.eol;
}
public void visitNotDescr(final NotDescr descr) {
this.template = new String();
if ( descr.getDescrs() != Collections.EMPTY_LIST ) {
this.template = "<not>" + processDescrList( descr.getDescrs() ) + "</not>";
} else {
this.template = "<not> </not>";
}
}
public void visitOrDescr(final OrDescr descr) {
this.template = new String();
if ( descr.getDescrs() != Collections.EMPTY_LIST ) {
if ( !this.patternContext ) this.template = "<or-conditional-element>" + processDescrList( descr.getDescrs() ) + "</or-conditional-element>";
else this.template = "<or-constraint-connective>" + processDescrList( descr.getDescrs() ) + "</or-constraint-connective>";
}
}
public void visitPackageDescr(final PackageDescr packageDescr) {
final String packageName = packageDescr.getName();
final String xmlString = "<?xml version=\"1.0\" encoding=\"UTF-8\"?> " + XmlDumper.eol + " <package name=\"" + packageName + "\" " + XmlDumper.eol + "\txmlns=\"http://drools.org/drools-5.0\" " + XmlDumper.eol
+ "\txmlns:xs=\"http://www.w3.org/2001/XMLSchema-instance\" " + XmlDumper.eol + "\txs:schemaLocation=\"http://drools.org/drools-5.0 drools.org/drools-5.0.xsd\"> " + XmlDumper.eol;
appendXmlDump( xmlString );
appendXmlDump( processImportsList( packageDescr.getImports() ) );
appendXmlDump( processGlobalsList( packageDescr.getGlobals() ) );
appendXmlDump( processFunctionImportsList( packageDescr.getFunctionImports() ));
appendXmlDump( processFunctionsList( packageDescr.getFunctions() ) );
appendXmlDump( processRules( packageDescr.getRules() ) );
appendXmlDump( "</package>" );
}
public void visitPredicateDescr(final PredicateDescr descr) {
this.template = new String();
this.template = "<predicate>" + replaceIllegalChars( (String) descr.getContent() ) + "</predicate>" + XmlDumper.eol;
}
public void visitReturnValueRestrictionDescr(final ReturnValueRestrictionDescr descr) {
this.template = new String();
this.template = "<return-value-restriction evaluator=\"" + replaceIllegalChars( descr.getEvaluator() ) + "\" >" + replaceIllegalChars( (String) descr.getContent() ) + "</return-value-restriction>" + XmlDumper.eol;
}
public void visitQueryDescr(final QueryDescr descr) {
this.template = new String();
this.template = "<query name=\"" + descr.getName() + "\">" + "<lhs>" + processDescrList( descr.getLhs().getDescrs() ) + "</lhs>" + "</query>";
}
private String processRules(final List rules) {
String ruleList = "";
for ( final Iterator iterator = rules.iterator(); iterator.hasNext(); ) {
final RuleDescr ruleDescr = (RuleDescr) iterator.next();
String rule = "<rule name=\"" + ruleDescr.getName() + "\">" + XmlDumper.eol;
final String attribute = processAttribute( ruleDescr.getAttributes().values() );
String lhs = "";
if ( ruleDescr.getLhs().getDescrs() != Collections.EMPTY_LIST ) {
lhs = "<lhs>" + processDescrList( ruleDescr.getLhs().getDescrs() ) + "</lhs>";
} else {
lhs = "<lhs> </lhs>";
}
final String rhs = "<rhs>" + replaceIllegalChars( (String) ruleDescr.getConsequence() ) + "</rhs>" + XmlDumper.eol;
rule += attribute;
rule += lhs;
rule += rhs;
rule += "</rule>";
ruleList += rule;
}
return ruleList + XmlDumper.eol;
}
private String processFieldConstraint(final List list) {
String descrString = "";
for ( final Iterator it = list.iterator(); it.hasNext(); ) {
final Object temp = it.next();
visit( temp );
descrString += this.template;
}
return descrString;
}
public void visitRestrictionConnectiveDescr(final RestrictionConnectiveDescr descr) {
this.template = new String();
final List restrictions = descr.getRestrictions();
final String xmlTag = descr.getConnective() == RestrictionConnectiveDescr.OR ? RestrictionConnectiveHandler.OR : RestrictionConnectiveHandler.AND;
if ( restrictions != Collections.EMPTY_LIST ) {
this.template = "<" + xmlTag + ">";
this.template += processDescrList( restrictions );
this.template += "</" + xmlTag + ">";
}
}
private String processDescrList(final List descr) {
String descrString = "";
for ( final Iterator iterator = descr.iterator(); iterator.hasNext(); ) {
visit( iterator.next() );
descrString += this.template;
descrString += XmlDumper.eol;
}
return descrString + XmlDumper.eol;
}
private String processFunctionsList(final List functions) {
String functionList = "";
for ( final Iterator iterator = functions.iterator(); iterator.hasNext(); ) {
visit( iterator.next() );
functionList += this.template;
}
return functionList + XmlDumper.eol;
}
private String processAttribute(final Collection<AttributeDescr> attributes ) {
String attributeList = "";
for ( final AttributeDescr attributeDescr : attributes) {
visit( attributeDescr );
attributeList += this.template;
}
return attributeList + XmlDumper.eol;
}
private String processParameters(final List parameterNames,
final List parameterTypes) {
String paramList = "";
int i = 0;
for ( final Iterator iterator = parameterNames.iterator(); iterator.hasNext(); i++ ) {
final String paramName = (String) iterator.next();
final String paramType = (String) parameterTypes.get( i );
final String paramTemplate = "<parameter identifier=\"" + paramName + "\" type=\"" + paramType + "\" />" + XmlDumper.eol;
paramList += paramTemplate;
}
return paramList + XmlDumper.eol;
}
private String processFunctionImportsList(final List imports) {
String importList = "";
for ( final Iterator it = imports.iterator(); it.hasNext(); ) {
final String importString = ((FunctionImportDescr) it.next()).getTarget();
final String importTemplate = "<importfunction name=\"" + importString + "\"/>" + XmlDumper.eol;
importList += importTemplate;
}
return importList + XmlDumper.eol;
}
private String processGlobalsList(final List globals) {
String globalList = "";
for ( final Iterator iterator = globals.iterator(); iterator.hasNext(); ) {
final GlobalDescr global = (GlobalDescr) iterator.next();
final String identifier = global.getIdentifier();
final String type = global.getType();
final String globalTemplate = "<global identifier=\"" + identifier + "\" type=\"" + type + "\" />" + XmlDumper.eol;
globalList += globalTemplate;
}
return globalList + XmlDumper.eol;
}
private String processImportsList(final List imports) {
String importList = "";
for ( final Iterator iterator = imports.iterator(); iterator.hasNext(); ) {
final String importString = ((ImportDescr) iterator.next()).getTarget();
final String importTemplate = "<import name=\"" + importString + "\" /> " + XmlDumper.eol;
importList += importTemplate;
}
return importList + XmlDumper.eol;
}
private void appendXmlDump(final String temp) {
this.xmlDump.append( temp );
}
/**
* Replace illegal xml characters with their escaped equivalent
* <P>The escaped characters are :
* <ul>
* <li> <
* <li> >
* <li> &
* </ul>
* </p>
* @author <a href="mailto:prietor@gmail.com">Author Javier Prieto</a>
*/
public static String replaceIllegalChars(final String code) {
final StringBuilder sb = new StringBuilder();
if ( code != null ) {
final int n = code.length();
for ( int i = 0; i < n; i++ ) {
final char c = code.charAt( i );
switch ( c ) {
case '<' :
sb.append( "<" );
break;
case '>' :
sb.append( ">" );
break;
case '&' :
sb.append( "&" );
break;
default :
sb.append( c );
break;
}
}
} else {
sb.append( "null" );
}
return sb.toString();
}
}