ECHONEST api 4 NULL指针异常

Below is my code, I'm not understanding the cause of the "ECHONEST api 4 NULL pointer exception":

下面是我的代码,我不理解“ECHONEST api 4 NULL指针异常”的原因:

package com.main;

import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.List;
import  java.util.Map;
import com.echonest.api.v4.EchoNestAPI;
import com.echonest.api.v4.EchoNestException;
import com.echonest.api.v4.Track;
import com.echonest.api.v4.TrackAnalysis;


public class SongAnalysis {
    private static final String API_KEY = "14CPBOK0IFN0HRC0R";

    public String getTempo(String fileName){
        return null;
    }

    public static void main (String [] args)throws EchoNestException, IOException{

        EchoNestAPI echoNest = new EchoNestAPI(API_KEY);
        File file = new File("C:\\Users\\wooh\\workspace\\SongAnalysis\\songs\\b.mp3");
        Track track = echoNest.uploadTrack(file,false );
        track.waitForAnalysis(30000);
        TrackAnalysis a = track.getAnalysis();
        System.out.println("Tempo" + a.getTempo());
    }
}

1 个解决方案

#1

The likely occurrences of your NPE are:

NPE可能出现的情况是:

echoNest is null.

echoNest为null。

track is null.

track为null。

a is null.

a为空。

You would want to pinpoint the specific location that your NullPointerException occurs, then ensure that when you instantiate the object, the object you need is being returned.

您可能想要确定发生NullPointerException的特定位置,然后确保在实例化对象时,返回所需的对象。

#1