驗證時，MongoDB Java驅動程序3.0無法捕獲異常

Question

我非常困惑o_0嘗試通過Java驅動程序進行身份驗證時，存在捕獲異常的問題。 如您所見，即使Throwable類也不起作用

private MongoClient mongoClient;
private MongoDatabase mongoDatabase;



public MongoConnection(String login, String password) {

    try {
        mongoClient = new MongoClient(asList(new ServerAddress("localhost"), new ServerAddress("localhost:27017")),
                singletonList(MongoCredential.createCredential(login,
                        "cookbook",
                        password.toCharArray())));

        this.mongoDatabase = mongoClient.getDatabase("cookbook");
    } catch (Throwable e) {
        System.out.println("exception");
    }
}

仍然沒有捕捉到異常

 INFO: Adding discovered server localhost:27017 to client view of cluster
 Jan 29, 2016 7:46:27 PM com.mongodb.diagnostics.logging.JULLogger log
 INFO: Exception in monitor thread while connecting to server      localhost:27017
 com.mongodb.MongoSecurityException: Exception authenticating       MongoCredential{mechanism=null, userName='asdasdasdasd', source='cookbook',      password=<hidden>, mechanismProperties={}}
at com.mongodb.connection.SaslAuthenticator.authenticate(SaslAuthenticator.java:61)
at com.mongodb.connection.DefaultAuthenticator.authenticate(DefaultAuthenticator.java:32)
at com.mongodb.connection.InternalStreamConnectionInitializer.authenticateAll(InternalStreamConnectionInitializer.java:99)
at com.mongodb.connection.InternalStreamConnectionInitializer.initialize(InternalStreamConnectionInitializer.java:44)
at com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:115)
at com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:127)
at java.lang.Thread.run(Thread.java:745)
 Caused by: com.mongodb.MongoCommandException: Command failed with error 18:    'Authentication failed.' on server localhost:27017. The full response is { "ok" : 0.0, "code" : 18, "errmsg" : "Authentication failed." }
at com.mongodb.connection.CommandHelper.createCommandFailureException(CommandHelper.java:170)
at com.mongodb.connection.CommandHelper.receiveCommandResult(CommandHelper.java:123)
at com.mongodb.connection.CommandHelper.executeCommand(CommandHelper.java:32)
at com.mongodb.connection.SaslAuthenticator.sendSaslStart(SaslAuthenticator.java:95)
at com.mongodb.connection.SaslAuthenticator.authenticate(SaslAuthenticator.java:45)

Answer 1

MongoDB Java API的最新版本在單獨的守護程序監視線程中引發連接異常，這就是為什么您無法捕獲它的原因-運行程序位於堆棧跟蹤中： com.mongodb.connection.DefaultServerMonitor $ ServerMonitorRunnable.run

要監視MongoDB客戶端是否有異常，您可以添加一個偵聽器，該偵聽器將允許您對可能發生的任何異常采取行動，並在需要時隨時檢查連接狀態。 您仍然將無法捕獲這些異常，但是您的應用程序至少會意識到它們。 需要注意的一件事是建立連接（或失敗）可能需要一些時間，因此，如果您只想創建一次性使用的連接，我建議您實施一個睡眠循環以檢查連接是否正常。以及失敗/異常狀態。 我使用版本3.3（ https://api.mongodb.com/java/3.3/ ）編寫了此解決方案：

public class MongoStatusListener implements ServerListener {

    private boolean available = false;

    public boolean isAvailable() {
        return available;
    }

    @Override
    public void serverOpening(ServerOpeningEvent event) {}

    @Override
    public void serverClosed(ServerClosedEvent event) {}

    @Override
    public void serverDescriptionChanged(ServerDescriptionChangedEvent event) {

        if (event.getNewDescription().isOk()) {
            available = true;
        } else if (event.getNewDescription().getException() != null) {
            //System.out.println("exception: " + event.getNewDescription().getException().getMessage());
            available = false;
        }
    }
}

public MongoClient getMongoClient(String login, String password) {

    if (mongoClient != null) {
        return mongoClient;
    }
    MongoClientOptions.Builder optionsBuilder = new MongoClientOptions.Builder();
    MongoStatusListener mongoStatusListener = new MongoStatusListener();
    optionsBuilder.addServerListener(mongoStatusListener);

    this.mongoClient = new MongoClient(asList(new ServerAddress("localhost"), new ServerAddress("localhost:27017")),
        singletonList(MongoCredential.createCredential(
        login,
        "cookbook",
        password.toCharArray())
    ), optionsBuilder.build());

    this.mongoDatabase = mongoClient.getDatabase("cookbook");
    return mongoClient;
}

public boolean isAvailable() {
    return mongoStatusListener.isAvailable();
}