android okhttp有预连接这种操作么提前ssl握手

Yes, Android OkHttp supports connection pooling and pre-connecting to a host to reduce the overhead of SSL/TLS handshakes. This is achieved through the use of the ConnectionPool and ConnectionSpec classes.

To enable connection pooling, you can create a new ConnectionPool instance and set it as the connection pool for your OkHttpClient:

ConnectionPool connectionPool = new ConnectionPool();
OkHttpClient okHttpClient = new OkHttpClient.Builder().connectionPool(connectionPool).build();

By default, connection pooling is enabled and the maximum number of idle connections per address is set to 5.

To pre-connect to a host, you can use the ConnectionSpec class to specify the SSL/TLS configuration for the connection and create a new Connection instance:

ConnectionSpec connectionSpec = new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS).build();
Address address = new Address(host, port);
Connection connection = new Connection.Builder().address(address).connectionSpecs(Collections.singletonList(connectionSpec)).build();

You can then use this Connection instance to perform requests:

Request request = new Request.Builder().url(url).build();
Call call = okHttpClient.newCall(request);
call.enqueue(new Callback() {
    @Override
    public void onFailure(Call call, IOException e) {
        // Handle failure
    }

    @Override
    public void onResponse(Call call, Response response) throws IOException {
        // Handle response
    }
});
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