/**
* Builds and returns an Eval Conditional Element
*
* @param context The current build context
* @param utils The current build utils instance
* @param patternBuilder not used by EvalBuilder
* @param descr The Eval Descriptor to build the eval conditional element from
* @return the Eval Conditional Element
*/
public RuleConditionElement build(
final RuleBuildContext context, final BaseDescr descr, final Pattern prefixPattern) {
// it must be an EvalDescr
final EvalDescr evalDescr = (EvalDescr) descr;
try {
MVELDialect dialect = (MVELDialect) context.getDialect(context.getDialect().getId());
Map<String, Declaration> decls =
context.getDeclarationResolver().getDeclarations(context.getRule());
AnalysisResult analysis =
context
.getDialect()
.analyzeExpression(
context,
evalDescr,
evalDescr.getContent(),
new BoundIdentifiers(
context.getDeclarationResolver().getDeclarationClasses(decls),
context.getPackageBuilder().getGlobals()));
Collection<Declaration> col = decls.values();
Declaration[] previousDeclarations = (Declaration[]) col.toArray(new Declaration[col.size()]);
MVELCompilationUnit unit =
dialect.getMVELCompilationUnit(
(String) evalDescr.getContent(), analysis, previousDeclarations, null, null, context);
final EvalCondition eval = new EvalCondition(previousDeclarations);
MVELEvalExpression expr = new MVELEvalExpression(unit, dialect.getId());
eval.setEvalExpression(expr);
MVELDialectRuntimeData data =
(MVELDialectRuntimeData)
context
.getPkg()
.getDialectRuntimeRegistry()
.getDialectData(context.getDialect().getId());
data.addCompileable(eval, expr);
expr.compile(context.getPackageBuilder().getRootClassLoader());
return eval;
} catch (final Exception e) {
context
.getErrors()
.add(
new DescrBuildError(
context.getParentDescr(),
evalDescr,
e,
"Unable to build expression for 'eval':"
+ e.getMessage()
+ " '"
+ evalDescr.getContent()
+ "'"));
return null;
}
}
/**
* Builds and returns an Eval Conditional Element
*
* @param context The current build context
* @param utils The current build utils instance
* @param patternBuilder not used by EvalBuilder
* @param descr The Eval Descriptor to build the eval conditional element from
* @return the Eval Conditional Element
*/
public RuleConditionElement build(
final RuleBuildContext context, final BaseDescr descr, final Pattern prefixPattern) {
Appendable builder = new StringBuilderAppendable();
EvalDescr edescr = (EvalDescr) descr;
FunctionHandlers.dump((LispForm) edescr.getContent(), builder, true);
edescr.setContent(builder.toString());
return super.build(context, descr, prefixPattern);
}
/**
* Builds and returns an Eval Conditional Element
*
* @param context The current build context
* @param utils The current build utils instance
* @param patternBuilder not used by EvalBuilder
* @param descr The Eval Descriptor to build the eval conditional element from
* @return the Eval Conditional Element
*/
public RuleConditionElement build(
final RuleBuildContext context, final BaseDescr descr, final Pattern prefixPattern) {
// it must be an EvalDescr
final EvalDescr evalDescr = (EvalDescr) descr;
try {
final DroolsMVELFactory factory =
new DroolsMVELFactory(
context.getDeclarationResolver().getDeclarations(),
null,
context.getPkg().getGlobals());
Dialect.AnalysisResult analysis =
context
.getDialect()
.analyzeExpression(
context,
evalDescr,
evalDescr.getContent(),
new Set[] {
context.getDeclarationResolver().getDeclarations().keySet(),
context.getPkg().getGlobals().keySet()
});
final List[] usedIdentifiers = analysis.getBoundIdentifiers();
final Declaration[] declarations = new Declaration[usedIdentifiers[0].size()];
for (int i = 0, size = usedIdentifiers[0].size(); i < size; i++) {
declarations[i] =
context.getDeclarationResolver().getDeclaration((String) usedIdentifiers[0].get(i));
}
final EvalCondition eval = new EvalCondition(declarations);
Serializable expr =
((MVELDialect) context.getDialect())
.compile((String) evalDescr.getContent(), analysis, null, null, null, context);
eval.setEvalExpression(new MVELEvalExpression(expr, factory, context.getDialect().getId()));
return eval;
} catch (final Exception e) {
context
.getErrors()
.add(
new DescrBuildError(
context.getParentDescr(),
evalDescr,
e,
"Unable to build expression for 'eval' node '" + evalDescr.getContent() + "'"));
return null;
}
}
public void testSimpleExpression() {
final Package pkg = new Package("pkg1");
final RuleDescr ruleDescr = new RuleDescr("rule 1");
PackageBuilder pkgBuilder = new PackageBuilder(pkg);
final PackageBuilderConfiguration conf = pkgBuilder.getPackageBuilderConfiguration();
MVELDialect mvelDialect = (MVELDialect) pkgBuilder.getDialectRegistry().getDialect("mvel");
final InstrumentedBuildContent context =
new InstrumentedBuildContent(
conf, pkg, ruleDescr, pkgBuilder.getDialectRegistry(), mvelDialect);
final InstrumentedDeclarationScopeResolver declarationResolver =
new InstrumentedDeclarationScopeResolver();
final FieldExtractor extractor =
cache.getExtractor(Cheese.class, "price", getClass().getClassLoader());
final Pattern pattern = new Pattern(0, new ClassObjectType(int.class));
final Declaration declaration = new Declaration("a", extractor, pattern);
final Map map = new HashMap();
map.put("a", declaration);
declarationResolver.setDeclarations(map);
context.setDeclarationResolver(declarationResolver);
final EvalDescr evalDescr = new EvalDescr();
evalDescr.setContent("a == 10");
final MVELEvalBuilder builder = new MVELEvalBuilder();
final EvalCondition eval = (EvalCondition) builder.build(context, evalDescr);
final RuleBase ruleBase = RuleBaseFactory.newRuleBase();
final WorkingMemory wm = ruleBase.newStatefulSession();
final Cheese cheddar = new Cheese("cheddar", 10);
final InternalFactHandle f0 = (InternalFactHandle) wm.insert(cheddar);
final ReteTuple tuple = new ReteTuple(f0);
Object evalContext = eval.createContext();
assertTrue(eval.isAllowed(tuple, wm, evalContext));
cheddar.setPrice(9);
wm.update(f0, cheddar);
assertFalse(eval.isAllowed(tuple, wm, evalContext));
}
/**
* Builds and returns an Eval Conditional Element
*
* @param context The current build context
* @param utils The current build utils instance
* @param patternBuilder not used by EvalBuilder
* @param descr The Eval Descriptor to build the eval conditional element from
* @return the Eval Conditional Element
*/
public RuleConditionElement build(
final RuleBuildContext context, final BaseDescr descr, final Pattern prefixPattern) {
// it must be an EvalDescr
final EvalDescr evalDescr = (EvalDescr) descr;
final String className = "eval" + context.getNextId();
evalDescr.setClassMethodName(className);
Map<String, Declaration> decls =
context.getDeclarationResolver().getDeclarations(context.getRule());
AnalysisResult analysis =
context
.getDialect()
.analyzeExpression(
context,
evalDescr,
evalDescr.getContent(),
new BoundIdentifiers(
context.getDeclarationResolver().getDeclarationClasses(decls),
context.getPackageBuilder().getGlobals()));
final BoundIdentifiers usedIdentifiers = analysis.getBoundIdentifiers();
final Declaration[] declarations = decls.values().toArray(new Declaration[decls.size()]);
Arrays.sort(declarations, SortDeclarations.instance);
final EvalCondition eval = new EvalCondition(declarations);
final Map map =
createVariableContext(
className,
(String) evalDescr.getContent(),
context,
declarations,
null,
usedIdentifiers.getGlobals(),
null);
generatTemplates("evalMethod", "evalInvoker", context, className, map, eval, descr);
return eval;
}
public void visitEvalDescr(final EvalDescr descr) {
this.template = new String();
this.template = "<eval>" + descr.getText() + "</eval>" + XmlDumper.eol;
}
/**
* Builds and returns an Eval Conditional Element
*
* @param context The current build context
* @param utils The current build utils instance
* @param patternBuilder not used by EvalBuilder
* @param descr The Eval Descriptor to build the eval conditional element from
* @return the Eval Conditional Element
*/
public RuleConditionElement build(
final RuleBuildContext context, final BaseDescr descr, final Pattern prefixPattern) {
boolean typesafe = context.isTypesafe();
// it must be an EvalDescr
final EvalDescr evalDescr = (EvalDescr) descr;
try {
MVELDialect dialect = (MVELDialect) context.getDialect(context.getDialect().getId());
Map<String, Declaration> decls =
context.getDeclarationResolver().getDeclarations(context.getRule());
AnalysisResult analysis =
context
.getDialect()
.analyzeExpression(
context,
evalDescr,
evalDescr.getContent(),
new BoundIdentifiers(
context.getDeclarationResolver().getDeclarationClasses(decls),
context.getPackageBuilder().getGlobals()));
final BoundIdentifiers usedIdentifiers = analysis.getBoundIdentifiers();
int i = usedIdentifiers.getDeclrClasses().keySet().size();
Declaration[] previousDeclarations = new Declaration[i];
i = 0;
for (String id : usedIdentifiers.getDeclrClasses().keySet()) {
previousDeclarations[i++] = decls.get(id);
}
Arrays.sort(previousDeclarations, SortDeclarations.instance);
MVELCompilationUnit unit =
dialect.getMVELCompilationUnit(
(String) evalDescr.getContent(),
analysis,
previousDeclarations,
null,
null,
context,
"drools",
KnowledgeHelper.class,
false);
final EvalCondition eval = new EvalCondition(previousDeclarations);
MVELEvalExpression expr = new MVELEvalExpression(unit, dialect.getId());
eval.setEvalExpression(expr);
MVELDialectRuntimeData data =
(MVELDialectRuntimeData)
context.getPkg().getDialectRuntimeRegistry().getDialectData("mvel");
data.addCompileable(eval, expr);
expr.compile(data);
return eval;
} catch (final Exception e) {
copyErrorLocation(e, evalDescr);
context.addError(
new DescrBuildError(
context.getParentDescr(),
evalDescr,
e,
"Unable to build expression for 'eval':"
+ e.getMessage()
+ " '"
+ evalDescr.getContent()
+ "'"));
return null;
} finally {
context.setTypesafe(typesafe);
}
}
