com.google.gson.JsonSyntaxException: java.lang.NumberFormatException

grpc对象转java对象报错：

com.google.gson.JsonSyntaxException: java.lang.NumberFormatException
	at com.google.gson.internal.bind.TypeAdapters$17.read(TypeAdapters.java:419)
	at com.google.gson.internal.bind.TypeAdapters$17.read(TypeAdapters.java:410)
	at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.read(ReflectiveTypeAdapterFactory.java:131)
	at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:222)
	at com.google.gson.Gson.fromJson(Gson.java:932)
	at com.google.gson.Gson.fromJson(Gson.java:897)
	at com.google.gson.Gson.fromJson(Gson.java:846)
	at com.google.gson.Gson.fromJson(Gson.java:817)
	at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:771)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:749)
	at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:56)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:749)
	at org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:55)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:749)
	at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:95)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:749)
	at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:691)
	at io.grpc.stub.ServerCalls$UnaryServerCallHandler$UnaryServerCallListener.onHalfClose(ServerCalls.java:172)
	at io.grpc.PartialForwardingServerCallListener.onHalfClose(PartialForwardingServerCallListener.java:35)
	at io.grpc.ForwardingServerCallListener.onHalfClose(ForwardingServerCallListener.java:23)
	at io.grpc.ForwardingServerCallListener$SimpleForwardingServerCallListener.onHalfClose(ForwardingServerCallListener.java:40)
	at io.grpc.Contexts$ContextualizedServerCallListener.onHalfClose(Contexts.java:86)
	at io.grpc.PartialForwardingServerCallListener.onHalfClose(PartialForwardingServerCallListener.java:35)
	at io.grpc.ForwardingServerCallListener.onHalfClose(ForwardingServerCallListener.java:23)
	at io.grpc.ForwardingServerCallListener$SimpleForwardingServerCallListener.onHalfClose(ForwardingServerCallListener.java:40)
	at io.grpc.PartialForwardingServerCallListener.onHalfClose(PartialForwardingServerCallListener.java:35)
	at io.grpc.ForwardingServerCallListener.onHalfClose(ForwardingServerCallListener.java:23)
	at io.grpc.ForwardingServerCallListener$SimpleForwardingServerCallListener.onHalfClose(ForwardingServerCallListener.java:40)
	at io.grpc.PartialForwardingServerCallListener.onHalfClose(PartialForwardingServerCallListener.java:35)
	at io.grpc.ForwardingServerCallListener.onHalfClose(ForwardingServerCallListener.java:23)
	at io.grpc.ForwardingServerCallListener$SimpleForwardingServerCallListener.onHalfClose(ForwardingServerCallListener.java:40)
	at io.grpc.Contexts$ContextualizedServerCallListener.onHalfClose(Contexts.java:86)
	at io.grpc.internal.ServerCallImpl$ServerStreamListenerImpl.halfClosed(ServerCallImpl.java:331)
	at io.grpc.internal.ServerImpl$JumpToApplicationThreadServerStreamListener$1HalfClosed.runInContext(ServerImpl.java:820)
	at io.grpc.internal.ContextRunnable.run(ContextRunnable.java:37)
	at io.grpc.internal.SerializingExecutor.run(SerializingExecutor.java:123)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: java.lang.NumberFormatException: null
	at java.base/java.math.BigDecimal.<init>(BigDecimal.java:692)
	at java.base/java.math.BigDecimal.<init>(BigDecimal.java:471)
	at java.base/java.math.BigDecimal.<init>(BigDecimal.java:900)
	at com.google.gson.internal.bind.TypeAdapters$17.read(TypeAdapters.java:417)
	... 49 common frames omitted
Caused by: java.lang.ArrayIndexOutOfBoundsException: Index 0 out of bounds for length 0
	at java.base/java.math.BigDecimal.<init>(BigDecimal.java:519)
	... 52 common frames omitted

原因：JSON 数据似乎是有效的。问题可能出在 Gson 解析这个 JSON 数据时，由于某个字段期望的是 BigDecimal 类型，而传入的值格式不正确。我就是没传这个字段值，然后报错了，如果一定要不传，可以自定义一个BigDecimal类型适配器：

import com.google.gson.TypeAdapter;
import com.google.gson.stream.JsonReader;
import com.google.gson.stream.JsonWriter;
import java.io.IOException;
import java.math.BigDecimal;

public class BigDecimalTypeAdapter extends TypeAdapter<BigDecimal> {
    @Override
    public void write(JsonWriter out, BigDecimal value) throws IOException {
        if (value == null) {
            out.nullValue();
        } else {
            out.value(value);
        }
    }

    @Override
    public BigDecimal read(JsonReader in) throws IOException {
        try {
            String value = in.nextString();
            if (value == null || value.isEmpty()) {
                return BigDecimal.ZERO; // 或者根据需要返回默认值
            }
            return new BigDecimal(value);
        } catch (NumberFormatException | IllegalStateException e) {
            return BigDecimal.ZERO; // 或者根据需要返回默认值
        }
    }
}

将适配器注册到gson对象中：

好了，没有报错了