[Java] use Files.createTempFile instead

[wing328]

• use Files.createTempFile instead to avoid potential security issues.

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• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
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  ./mvnw clean package 
  ./bin/generate-samples.sh
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cc @bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10) @nmuesch (2021/01)

[spacether]

Looks good to me

[Sarangan0219]

Hi @wing328

Currently we are using openapi-generator 4.3.1, and when downloading JAVA SDK for endpoints with PDF files, we couldn't observe any temporary files in /tmp orvar/tmp folder. Could you please tell me how we can reproduce this issue ?

[wing328]

please try the latest stable version v5.3.1 instead and open a new issue for tracking if you need help from the community.

[Sarangan0219]

yes with stable version v5.3.1 we have no issues. I just want to analyze this issue in my environment with the previous versions. Could you please let me know the steps to reproduce this in previous versions ?

[wing328]

the issue was reported by a user and he didn't provide details on how exactly he uncovered the issue.