[QUESTION]

我尝试使用API: JSON.toJSONString(javaObj);
fastjson2版本为: 2.0.25

发生报错如下:
java.lang.ArrayIndexOutOfBoundsException: -1
at com.alibaba.fastjson2.internal.asm.Frame.getConcreteOutputType(Frame.java:1062)
Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException:
Error has been observed at the following site(s):
|_ checkpoint ⇢ org.springframework.cloud.gateway.filter.WeightCalculatorWebFilter [DefaultWebFilterChain]
|_ checkpoint ⇢ HTTP GET "/itf/test" [ExceptionHandlingWebHandler]
Stack trace:
at com.alibaba.fastjson2.internal.asm.Frame.getConcreteOutputType(Frame.java:1062)
at com.alibaba.fastjson2.internal.asm.Frame.merge(Frame.java:1095)
at com.alibaba.fastjson2.internal.asm.MethodWriter.visitMaxs(MethodWriter.java:554)
at com.alibaba.fastjson2.writer.ObjectWriterCreatorASM.genMethodWriteJSONB(ObjectWriterCreatorASM.java:721)
at com.alibaba.fastjson2.writer.ObjectWriterCreatorASM.createObjectWriter(ObjectWriterCreatorASM.java:469)
at com.alibaba.fastjson2.writer.ObjectWriterProvider.getObjectWriter(ObjectWriterProvider.java:195)
at com.alibaba.fastjson2.JSON.toJSONString(JSON.java:2182)

请问可能是什么原因?

Start by reproducing JSON.toJSONString(javaObj) with fastjson2 2.0.25, using the stack trace as the entry point. Read com.alibaba.fastjson2.internal.asm.Frame.getConcreteOutputType and the callers in Frame.merge, MethodWriter.visitMaxs, and ObjectWriterCreatorASM. Done means identifying the missing input detail or confirmed cause and documenting a reproducible diagnosis.

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