cloudant - 如何将 Java 应用程序（Java 代码）连接到 cloudant？

Question

我在 Eclipse 中有 java 代码，我已经完成了 eclipse 和 IBM bluemix cloudant 服务之间所需的所有设置我不知道如何更新我的代码以在 eclipse 中启用 cloudant 有人可以帮忙吗？

Answer 1

您需要在项目源目录下的 CloudantClient.java 文件中添加一段代码。请在 CloudantClient 类中添加这些行：

String VCAP_SERVICES = System.getenv("VCAP_SERVICES");
                JSONObject vcap;
                vcap = (JSONObject) JSONObject.parse(VCAP_SERVICES);
                cloudant = (JSONArray) vcap.get("cloudantNoSQULDB");
                cloudantInstance = (JSONObject) cloudant.get(0);
                cloudantCredentials = (JSONObject) cloudantInstance.get("credentials");

您也可以将这段代码放入 try catch 循环中。

try {
                String VCAP_SERVICES = System.getenv("VCAP_SERVICES");
                JSONObject vcap;
                vcap = (JSONObject) JSONObject.parse(VCAP_SERVICES);
                cloudant = (JSONArray) vcap.get("cloudantNoSQULDB");
                cloudantInstance = (JSONObject) cloudant.get(0);
                cloudantCredentials = (JSONObject) cloudantInstance.get("credentials");
                } 
            catch (IOException e) {
                e.printStackTrace();
            }

我希望它有效！

Answer 2

您可以使用 Bluemix 配置解析器库来自动解析 VCAP_SERVICES 环境变量 ( https://github.com/icha024/bluemix-config-parser )

它将凌乱的代码简化为...

String username = BluemixConfigStore.getConfig().getCloudantNoSQLDB()
                    .getCredentials().getUsername();
String password = BluemixConfigStore.getConfig().getCloudantNoSQLDB()
                    .getCredentials().getPassword();    

然后，您可以像往常一样从中创建 Cloudant 客户端：

CloudantClient cloudantClient = ClientBuilder.account(username)
                                  .username(username)
                                  .password(password)
                                  .build();

Answer 3

您需要使用 bluemix 中使用的 VCAP_SERVICES 环境变量，如下所示：

private JSONArray cloudant;
private JSONObject cloudantInstance;
private JSONObject cloudantCredentials;
public CloudantClient()
{
    this.httpClient = null;

    try {
        String VCAP_SERVICES = System.getenv("VCAP_SERVICES");
        JSONObject vcap;
        vcap = (JSONObject) JSONObject.parse(VCAP_SERVICES);
        cloudant = (JSONArray) vcap.get("cloudantNoSQLDB");
        cloudantInstance = (JSONObject) cloudant.get(0);
        cloudantCredentials = (JSONObject) cloudantInstance.get("credentials");
    } catch (IOException e) {
        e.printStackTrace();
    }
    this.port = Config.CLOUDANT_PORT;
    this.host = (String) cloudantCredentials.get("host");
    this.username = (String) cloudantCredentials.get("username");
    this.password = (String) cloudantCredentials.get("password");
    this.name = Config.CLOUDANT_NAME;
    this.dbc = this.createDBConnector(); 
}