后台返回出现JSON前边乱码请问怎么解决

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使用fastJson1.2.83的时候返回的json是正常的，用fastJson2.0.45就出现乱码请问怎处理

Start with the reported response path and compare the behavior of fastjson 1.2.83 and 2.0.45 using the example shown in the issue image. Identify whether the leading garbage is produced during JSON serialization or by response encoding, then document a reproducible case and verify that the response contains valid JSON without the extra characters.

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