Ensure JDK 6 compatibility of regular expression used in QueryUtils

Caused By: java.util.regex.PatternSyntaxException: Look-behind group does not have an obvious maximum length near index 58
\s+\w+\([0-9a-zA-z\._,\s']+\)\s+[as|AS]+\s+(?<alias>[\w\.]+)
                                                          ^
        at java.util.regex.Pattern.error(Pattern.java:1713)
        at java.util.regex.Pattern.group0(Pattern.java:2488)
        at java.util.regex.Pattern.sequence(Pattern.java:1806)
        at java.util.regex.Pattern.expr(Pattern.java:1752)
        at java.util.regex.Pattern.compile(Pattern.java:1460)
        at java.util.regex.Pattern.<init>(Pattern.java:1133)
        at java.util.regex.Pattern.compile(Pattern.java:823)
        at org.springframework.data.jpa.repository.query.QueryUtils.<clinit>(QueryUtils.java:164)
        at org.springframework.data.jpa.repository.query.JpaQueryMethod.assertParameterNamesInAnnotatedQuery(JpaQueryMethod.java:102)
        at org.springframework.data.jpa.repository.query.JpaQueryMethod.<init>(JpaQueryMethod.java:95)
        at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$AbstractQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:77)
        at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.<init>(RepositoryFactorySupport.java:435)
        at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:220)
        at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.initAndReturn(RepositoryFactoryBeanSupport.java:266)
        at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.afterPropertiesSet(RepositoryFactoryBeanSupport.java:252)
        at org.springframework.data.jpa.repository.support.JpaRepositoryFactoryBean.afterPropertiesSet(JpaRepositoryFactoryBean.java:92)