Exception in thread "main" [Error: illegal escape sequence: a]

[Near : {... "\a" ....}]

               ^

[Line: 1, Column: 3]

at org.mvel2.util.ParseTools.handleEscapeSequence(ParseTools.java:889)

at org.mvel2.util.ParseTools.handleStringEscapes(ParseTools.java:1533)

at org.mvel2.compiler.AbstractParser.nextToken(AbstractParser.java:1105)

at org.mvel2.compiler.ExpressionCompiler._compile(ExpressionCompiler.java:128)

at org.mvel2.compiler.ExpressionCompiler.compile(ExpressionCompiler.java:62)

at org.mvel2.MVEL.analysisCompile(MVEL.java:670)

at org.mvel2.MVEL.analysisCompile(MVEL.java:674)

at org.drools.rule.builder.PatternBuilder.setInputs(PatternBuilder.java:942)

at org.drools.rule.builder.PatternBuilder.buildRelationalExpression(PatternBuilder.java:638)

at org.drools.rule.builder.PatternBuilder.build(PatternBuilder.java:588)

at org.drools.rule.builder.PatternBuilder.processConstraintsAndBinds(PatternBuilder.java:449)

at org.drools.rule.builder.PatternBuilder.build(PatternBuilder.java:296)

at org.drools.rule.builder.PatternBuilder.build(PatternBuilder.java:118)

at org.drools.rule.builder.GroupElementBuilder.build(GroupElementBuilder.java:65)

at org.drools.rule.builder.RuleBuilder.build(RuleBuilder.java:80)

at org.drools.compiler.PackageBuilder.addRule(PackageBuilder.java:2503)

at org.drools.compiler.PackageBuilder.addPackage(PackageBuilder.java:847)

at org.drools.compiler.PackageBuilder.addPackageFromDrl(PackageBuilder.java:443)

at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:626)

at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:41)

at foobar.Main.setup(Main.java:68)

at foobar.Main.main(Main.java:124)