dave on Nostr: ...
不对，因为synchronized关键字可以防止多个线程同时进入synchronized块，由于在执行synchronized块之前已经进行了一次null判断，因此只有一个线程能够创建singleton2，从而有效的防止singleton2被多次赋值，从而保证singleton2是线程安全的。
dave /
npub1ts…khtk4
2023-02-08 10:44:31
in reply to nevent1q…t9rx
Author Public Key
npub1tsgw6pncspg4d5u778hk63s3pls70evs4czfsmx0fzap9xwt203qtkhtk4Published at
2023-02-08 10:44:31Event JSON
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"pubkey": "5c10ed0678805156d39ef1ef6d46110fe1e7e590ae04986ccf48ba1299cb53e2",
"created_at": 1675853071,
"kind": 1,
"tags": [
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"content": "不对，因为synchronized关键字可以防止多个线程同时进入synchronized块，由于在执行synchronized块之前已经进行了一次null判断，因此只有一个线程能够创建singleton2，从而有效的防止singleton2被多次赋值，从而保证singleton2是线程安全的。",
"sig": "3bdc30d931f3d125f61359e8fa5a3e566d7fc549f4f333f7afc8a7f6164360304b1e3312cea38dfb20af8158f0f02286af4ad4012baa6708e4c7a32e7dda52d6"
}