环境:
jdk 1.8
avro和jackson的maven依赖如下:
org.apache.avro
avro
1.7.4
com.fasterxml.jackson.core
jackson-annotations
2.4.0
com.fasterxml.jackson.core
jackson-databind
2.4.1.3
avro的schema文件如下:
{"namespace": "idp.model",
"type": "record",
"name": "DtHourBasic",
"fields": [
{"name": "user_id", "type": "string"},
{"name": "hour", "type": "string"},
{"name": "app_cat_id", "type": "string"},
{"name": "app_id", "type": "string", "default": "null"},
{"name": "lac", "type":["string", "null"], "default": "null"},
{"name": "ci", "type":["string", "null"], "default": "null"},
{"name": "city_code", "type":["string", "null"], "default": "null"},
{"name": "frequency", "type": "int"},
{"name": "max_time", "type": "string"},
{"name": "min_time", "type": "string"},
{"name": "c_city_code", "type": "string"}
]
}
报错如下:
运行代码:
public class JacksonUtils {
private final static ObjectMapper mapper = new ObjectMapper();
static {
mapper.configure(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY, true);
mapper.configure(DeserializationFeature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT, true);
}
/**
* 将对象转换成json字符串,用于将发送的报文打印出到日志
*/
public static String toString(Object object) {
String result = null;
if (null == object)
return result;
try {
result = mapper.writeValueAsString(object);
} catch (JsonProcessingException e) {
System.out.println("对象转换成json字符串出错");
e.printStackTrace();
}
return result;
}
}
DtHourBasic baseObj = DtHourBasic.newBuilder().setUserId("188xxx")
.setAppCatId("01")
.setAppId("07")
.setLac("123")
.setCi("123456")
.setCCityCode("0512")
.setHour("00")
.setFrequency(3)
.setMaxTime("201909090510")
.setMinTime("201909090505")
.setCityCode("510104")
.build();
System.out.println(JacksonUtils.toString(result));
代码运行时,报错如下:
com.fasterxml.jackson.databind.JsonMappingException: Not a union: {"type":"record","name":"DtHourBasic","namespace":"idp.model","fields":[{"name":"user_id","type":"string"},{"name":"hour","type":"string"},{"name":"app_cat_id","type":"string"},{"name":"app_id","type":"string","default":"null"},{"name":"lac","type":["string","null"],"default":"null"},{"name":"ci","type":["string","null"],"default":"null"},{"name":"city_code","type":["string","null"],"default":"null"},{"name":"frequency","type":"int"},{"name":"max_time","type":"string"},{"name":"min_time","type":"string"},{"name":"c_city_code","type":"string"}]} (through reference chain: idp.model.DtHourBasic["schema"]->org.apache.avro.RecordSchema["types"])
at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:232)
at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:197)
at com.fasterxml.jackson.databind.ser.std.StdSerializer.wrapAndThrow(StdSerializer.java:187)
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:647)
at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:152)
at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:505)
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:639)
at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:152)
at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:114)
at com.fasterxml.jackson.databind.ObjectMapper._configAndWriteValue(ObjectMapper.java:2866)
at com.fasterxml.jackson.databind.ObjectMapper.writeValueAsString(ObjectMapper.java:2323)
at com.dmp.utils.JacksonUtils.toString(JacksonUtils.java:33)
at com.dmp.TestHourProcess.testMergeBasicInfo(TestHourProcess.java:39)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:45)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:42)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:263)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:68)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:47)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222)
at org.junit.runners.ParentRunner.run(ParentRunner.java:300)
at org.junit.runner.JUnitCore.run(JUnitCore.java:157)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: org.apache.avro.AvroRuntimeException: Not a union: {"type":"record","name":"DtHourBasic","namespace":"idp.model","fields":[{"name":"user_id","type":"string"},{"name":"hour","type":"string"},{"name":"app_cat_id","type":"string"},{"name":"app_id","type":"string","default":"null"},{"name":"lac","type":["string","null"],"default":"null"},{"name":"ci","type":["string","null"],"default":"null"},{"name":"city_code","type":["string","null"],"default":"null"},{"name":"frequency","type":"int"},{"name":"max_time","type":"string"},{"name":"min_time","type":"string"},{"name":"c_city_code","type":"string"}]}
at org.apache.avro.Schema.getTypes(Schema.java:266)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:466)
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:639)
... 31 more
发现Jackson在序列化avro文件的时候,也会去序列号Schema中的属性,在网上找到了一篇blog,
参考地址为:https://www.jb51.net/article/149947.htm
尝试搞了一下,虽然不报错了,但是序列化后的json字符串中有些属性时重复的,头大!!!
{
"user_id":"188xxx",
"hour":"00",
"app_cat_id":"01",
"app_id":"07",
"lac":"123",
"ci":"123456",
"city_code":"510104",
"frequency":6,
"max_time":"201909090511",
"min_time":"201909090506",
"c_city_code":"0512",
"userId":"188xxx",
"appCatId":"01",
"appId":"07",
"ccityCode":"0512",
"maxTime":"201909090511",
"minTime":"201909090506",
"cityCode":"510104"
}
最后,发现Avro类自带的toString方法就可以直接序列化。。。
好吧,干了半天。。。
public abstract class SpecificRecordBase
implements SpecificRecord, Comparable, GenericRecord {
...
@Override
public String toString() {
return SpecificData.get().toString(this);
}
}
原生的API要多尝试啊。。。