定义流程启动规则，流转时报错，与format函数有关

localhost

concat('单据金额:',format('%.2f',relationValue('TBill',getProcessData1(),null,null,'FTotalAmount','/erp/scm/im/data')))

当FTotalAmount=0时，为什么报错啊，请帮看看是什么问题


Caused by: com.justep.model.exception.ModelException: 执行函数是出错：concat
        at com.justep.system.ksql.parser.ExpressionImpl.functionExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.constExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.unaryExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.multiExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.addExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.compExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.notExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.andExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.orExpression(Unknown Source)
        ... 55 more
Caused by: com.justep.model.exception.ModelException: 执行函数是出错：format
        at com.justep.system.ksql.parser.ExpressionImpl.functionExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.constExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.unaryExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.multiExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.addExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.compExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.notExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.andExpression(Unknown Source)
        at com.justep.system.ksql.parser.ExpressionImpl.orExpression(Unknown Source)
        ... 64 more
Caused by: java.lang.reflect.InvocationTargetException
        at sun.reflect.GeneratedMethodAccessor137.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:592)
        ... 73 more
Caused by: java.lang.IllegalArgumentException: Digits < 0
        at java.math.MathContext.<init>(MathContext.java:157)
        at java.math.MathContext.<init>(MathContext.java:141)
        at java.util.Formatter$FormatSpecifier.print(Formatter.java:3541)
        at java.util.Formatter$FormatSpecifier.print(Formatter.java:3460)
        at java.util.Formatter$FormatSpecifier.printFloat(Formatter.java:2716)
        at java.util.Formatter$FormatSpecifier.print(Formatter.java:2664)
        at java.util.Formatter.format(Formatter.java:2430)
        at java.util.Formatter.format(Formatter.java:2364)
        at java.lang.String.format(String.java:2558)
        at CommonFn.format(CommonFn.java:210)
        ... 76 more

jishuang

format('%.2f'这个是对浮点数进行操作的，0是整数，可以判断一下看看