<select id="sltTreatment" resultType="com.vitaminmd.sunny.core.bo.Treatment">

         select *

         from treatment

         where TRUE

         <if test="index == 'A'">

             AND ensubject IS NOT NULL AND ensubject &lt;&gt; ''

         </if>

     </select>

Caused by: java.lang.NumberFormatException: For input string: "A"

    at sun.misc.FloatingDecimal.readJavaFormatString(Unknown Source)

    at java.lang.Double.parseDouble(Unknown Source)

    at org.apache.ibatis.ognl.OgnlOps.doubleValue(OgnlOps.java:248)

    at org.apache.ibatis.ognl.OgnlOps.compareWithConversion(OgnlOps.java:137)

    at org.apache.ibatis.ognl.OgnlOps.isEqual(OgnlOps.java:178)

    at org.apache.ibatis.ognl.OgnlOps.equal(OgnlOps.java:548)

    at org.apache.ibatis.ognl.ASTEq.getValueBody(ASTEq.java:49)

    at org.apache.ibatis.ognl.SimpleNode.evaluateGetValueBody(SimpleNode.java:175)

    at org.apache.ibatis.ognl.SimpleNode.getValue(SimpleNode.java:213)

    at org.apache.ibatis.ognl.Ognl.getValue(Ognl.java:314)

    at org.apache.ibatis.ognl.Ognl.getValue(Ognl.java:394)

    at org.apache.ibatis.ognl.Ognl.getValue(Ognl.java:435)

    at org.apache.ibatis.ognl.Ognl.getValue(Ognl.java:414)

    at org.apache.ibatis.builder.xml.dynamic.ExpressionEvaluator.evaluateBoolean(ExpressionEvaluator.java:17)

    at org.apache.ibatis.builder.xml.dynamic.IfSqlNode.apply(IfSqlNode.java:15)

    at org.apache.ibatis.builder.xml.dynamic.MixedSqlNode.apply(MixedSqlNode.java:14)

    at org.apache.ibatis.builder.xml.dynamic.DynamicSqlSource.getBoundSql(DynamicSqlSource.java:22)

    at org.apache.ibatis.mapping.MappedStatement.getBoundSql(MappedStatement.java:198)

    at org.apache.ibatis.executor.BaseExecutor.createCacheKey(BaseExecutor.java:115)

    at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:90)

    at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:72)

    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:75)