问题描述
我正在使用。
我的架构有地图类型：
{"name": "MyData",
"type" : {"type": "map",
"values":{
"type": "record",
"name": "Person",
"fields":[
{"name": "name", "type": "string"},
{"name": "age", "type": "int"},
]
}
}
}
编译架构后，生成的Java类使用 CharSequence 作为 Map 键 c $ c> MyData 。
After compile the schema, the genated Java class use CharSequence as the key for the Map MyData.
在地图中使用 CharSequence 非常不方便作为键，有没有办法在？
It is very inconvenient to use CharSequence in Map as key, is there a way to generate String type key for Map in Apache Avro?
PS
问题是，例如 dataMap.containsKey（SOME_KEY）将返回 false 即使那里有这样的密钥，只是因为它是 CharSequence 。此外，使用现有密钥放置映射条目不会重新使用旧密钥。这就是为什么我说使用 CharSequence 作为密钥是不方便的。
Problem is that, for example dataMap.containsKey("SOME_KEY") will returns false even though there is such key there, just because it is CharSequence. Besides, put an map entry with a existing key doesn't relpace the old one. That's why I say it is inconvenient to use CharSequence as key.
推荐答案
是相关的。仍然使用CharSequence的要点是向后兼容性。
This JIRA discussion is relevant. The main point of CharSequence still being used is backwards-compatability.
和Charles Forsythe指出的一样，通过在模式中设置字符串属性，已经为必要时添加了一个变通方法。
And like Charles Forsythe pointed out, there has been added a workaround for when String is necessary, by setting the string property in the schema.
{ "type": "string", "avro.java.string": "String" }
这里的默认类型是他们自己的Utf8类。除了手动规范和，甚至有一个avro-tools编译选项， -string 选项：
The default type here is their own Utf8 class. In addition to manual specification and the pom.xml setting, there is even an avro-tools compile option for it, the -string option:
java -jar avro-tools.1.7.5.jar compile -string schema /path/to/schema .
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