jackson包问题

1.springmvc:

Handler dispatch failed; nested exception is java.lang.NoSuchMethodError: com.fasterxml.jackson.core.JsonGenerator.writeFieldId(J)V

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:982)

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)

at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)

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Caused by: java.lang.NoSuchMethodError: com.fasterxml.jackson.core.JsonGenerator.writeFieldId(J)V

at com.fasterxml.jackson.databind.ser.std.StdKeySerializers$Default.serialize(StdKeySerializers.java:180)

at com.fasterxml.jackson.databind.ser.std.MapSerializer.serializeFields(MapSerializer.java:707)

at com.fasterxml.jackson.databind.ser.std.MapSerializer.serialize(MapSerializer.java:639)

at com.fasterxml.jackson.databind.ser.std.MapSerializer.serialize(MapSerializer.java:33)

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[Request processing failed; nested exception is java.lang.IllegalStateException: getOutputStream() has already been called for this response] with root cause

java.lang.IllegalStateException: getOutputStream() has already been called for this response

解决：

1)版本 : 与spring相适应

2）加包

提示：如果是多模块开发，或许要install