ambari.interaction.NodeController.java Source code

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Here is the source code for ambari.interaction.NodeController.java

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/*
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package ambari.interaction;

import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import java.util.ArrayList;
import java.util.Map.Entry;
import java.util.Vector;

/**
 *
 * @author student
 */
public class NodeController {

    public static ArrayList<ComponentInformation> getListOfNodes() throws Exception {
        String url = "http://127.0.0.1:8080/api/v1/clusters/mycluster/services/HDFS/components/DATANODE?fields=host_components/HostRoles/desired_admin_state,host_components/HostRoles/state";
        String responseJson = HttpURLConnectionExample.sendGet(url);
        System.out.print(responseJson);
        JsonParser jsonParser = new JsonParser();
        JsonElement jsonTree = jsonParser.parse(responseJson);
        ArrayList<ComponentInformation> listOfCompoents = new ArrayList<ComponentInformation>();

        if (jsonTree.isJsonObject()) {
            JsonObject jsonObject = jsonTree.getAsJsonObject();
            JsonElement hostComponents = jsonObject.get("host_components");

            if (hostComponents.isJsonArray()) {
                JsonArray hostComponentsJsonArray = hostComponents.getAsJsonArray();
                System.out.println("\nStart");
                System.out.println(hostComponentsJsonArray);

                for (int i = 0; i < hostComponentsJsonArray.size(); i++) {
                    JsonElement hostComponentsElem = hostComponentsJsonArray.get(i);

                    if (hostComponentsElem.isJsonObject()) {
                        JsonObject jsonObjectElem = hostComponentsElem.getAsJsonObject();
                        JsonElement hostRolesElem = jsonObjectElem.get("HostRoles");

                        if (hostRolesElem.isJsonObject()) {
                            JsonObject hostRolesObjs = hostRolesElem.getAsJsonObject();
                            JsonElement componentNameElem = hostRolesObjs.get("component_name");
                            JsonElement hostNameElem = hostRolesObjs.get("host_name");
                            JsonElement stateElem = hostRolesObjs.get("state");

                            listOfCompoents.add(new ComponentInformation(componentNameElem.toString(),
                                    hostNameElem.toString(), stateElem.toString()));
                        }
                    }
                }
            }
        }

        return listOfCompoents;
    }

}