堆棧內存溢出
  簡體   English   中英

將txt文件讀入2d數組強制退出

[英]read txt file into 2d array force exit

 原文  2014-09-04 16:20:17  6   1    java/ android/ file/ text

問題描述

首先，我為我的英語不好對不起。 我想讀取txt文件並轉換為2d數組。 該代碼成功在Java上運行。 但是android模擬器發出警告消息：“抱歉！應用程序意外停止。請重試”

我該如何解決？ 謝謝

這是我的代碼： 

package com.example.hocam;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;

public class Konular extends ActionBarActivity {

  private ListView konuListe;
  private List<KonuBilgileri> konuBilgileri;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_konular);
    Bundle dersadi = getIntent().getExtras();
    String dersinadi= dersadi.getString("Ders");

   switch(dersinadi)  {
   case "Turkce": 
       KonuGetir turkce=new KonuGetir("turkce.txt");

       String[][] turkcekonular=turkce.getKonular();

      System.out.println(turkcekonular[0][0]);  // it is the problem and give error
       konuListe = (ListView) findViewById(R.id.konu_listesi);
        konuBilgileri = new ArrayList<KonuBilgileri>();
       konuBilgileri.add(new KonuBilgileri(turkcekonular[0][0],R.drawable.turkce, turkcekonular[0][1]));  // array is problem

        MyAdapter adapter = new MyAdapter(Konular.this, R.layout.custom_list_item, konuBilgileri);
       konuListe.setAdapter(adapter);

       break;

   }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.konular, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

}

 import java.io.File;
 import java.io.FileNotFoundException;
 import java.util.Scanner;

public class KonuGetir {
final int maxLines = 10100;
String[][] resultArray = new String[maxLines][];

public KonuGetir(String Ders){
      File file = new File(Ders);
        Scanner scanner;
        try {
            scanner = new Scanner(file,"utf-8");
             int linesCounter = 0;
                while (scanner.hasNextLine() && linesCounter < maxLines) {
                    resultArray[linesCounter] = scanner.nextLine().split("@");
                    linesCounter++;
                }
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

}
public String[][] getKonular()  {
    return resultArray;
}
}

日志文件： 

> 09-04 16:18:22.262: E/AndroidRuntime(1164): FATAL EXCEPTION: main
09-04 16:18:22.262: E/AndroidRuntime(1164): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.hocam/com.example.hocam.Konular}: java.lang.NullPointerException
09-04 16:18:22.262: E/AndroidRuntime(1164):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at android.os.Handler.dispatchMessage(Handler.java:99)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at android.os.Looper.loop(Looper.java:123)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at android.app.ActivityThread.main(ActivityThread.java:4627)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at java.lang.reflect.Method.invokeNative(Native Method)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at java.lang.reflect.Method.invoke(Method.java:521)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at dalvik.system.NativeStart.main(Native Method)
09-04 16:18:22.262: E/AndroidRuntime(1164): Caused by: java.lang.NullPointerException
09-04 16:18:22.262: E/AndroidRuntime(1164):     at com.example.hocam.Konular.onCreate(Konular.java:66)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
09-04 16:18:22.262: E/AndroidRuntime(1164):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
09-04 16:18:22.262: E/AndroidRuntime(1164):     ... 11 more
09-04 16:42:10.422: E/AndroidRuntime(1178): FATAL EXCEPTION: main
09-04 16:42:10.422: E/AndroidRuntime(1178): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.hocam/com.example.hocam.Konular}: java.lang.NullPointerException
09-04 16:42:10.422: E/AndroidRuntime(1178):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at android.os.Handler.dispatchMessage(Handler.java:99)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at android.os.Looper.loop(Looper.java:123)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at android.app.ActivityThread.main(ActivityThread.java:4627)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at java.lang.reflect.Method.invokeNative(Native Method)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at java.lang.reflect.Method.invoke(Method.java:521)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at dalvik.system.NativeStart.main(Native Method)
09-04 16:42:10.422: E/AndroidRuntime(1178): Caused by: java.lang.NullPointerException
09-04 16:42:10.422: E/AndroidRuntime(1178):     at com.example.hocam.Konular.onCreate(Konular.java:66)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
09-04 16:42:10.422: E/AndroidRuntime(1178):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
09-04 16:42:10.422: E/AndroidRuntime(1178):     ... 11 more
09-04 16:43:28.802: E/AndroidRuntime(1207): FATAL EXCEPTION: main
09-04 16:43:28.802: E/AndroidRuntime(1207): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.hocam/com.example.hocam.Konular}: java.lang.NullPointerException
09-04 16:43:28.802: E/AndroidRuntime(1207):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at android.os.Handler.dispatchMessage(Handler.java:99)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at android.os.Looper.loop(Looper.java:123)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at android.app.ActivityThread.main(ActivityThread.java:4627)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at java.lang.reflect.Method.invokeNative(Native Method)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at java.lang.reflect.Method.invoke(Method.java:521)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at dalvik.system.NativeStart.main(Native Method)
09-04 16:43:28.802: E/AndroidRuntime(1207): Caused by: java.lang.NullPointerException
09-04 16:43:28.802: E/AndroidRuntime(1207):     at com.example.hocam.Konular.onCreate(Konular.java:66)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
09-04 16:43:28.802: E/AndroidRuntime(1207):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
09-04 16:43:28.802: E/AndroidRuntime(1207):     ... 11 more

android清單文件： 

 <uses-permission android:name="android.permission.INTERNET" /> <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="21" /> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name=".MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <activity android:name=".YGS" android:label="@string/title_activity_ygs" > </activity> <activity android:name=".Konular" android:label="@string/title_activity_konular" > </activity> <activity android:name=".Video" android:screenOrientation="landscape" android:label="@string/title_activity_video" > </activity> </application>

1 個解決方案

解決方案1
 0  2014-09-04 23:25:09

您正在使用以下代碼： 

  String[][] turkcekonular=turkce.getKonular();

  System.out.println(turkcekonular[0][0]);

但是獲取java.lang.NullPointerException 。

這樣做的原因是因為getKonular()返回一個初始化為大小10100的數組，但是scanner不包含任何行，因此scanner.hasNextLine()為false。

這意味着turkcekonular[0]為空，因為它從未設置。 這意味着turkcekonular[0][0]試圖訪問空對象，因此拋出NullPointerException

在嘗試訪問該對象之前，應檢查該對象是否為null。 

 if(turkcekonular[0] != null)
      System.out.println(turkcekonular[0][0]);

以及發生此問題的位置。

（並且您應該弄清楚為什么不讀取您的文件。文件名稱正確並且存在於指定路徑中嗎？）

暫無
暫無

聲明:本站的技術帖子網頁，遵循CC BY-SA 4.0協議，如果您需要轉載，請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.

相關問題 將 .txt 文件讀入二維數組 java將txt文件（2D）讀入幾個2D數組 如何在 java 中將 a.txt 文件讀入二維數組？ 將 ascii 字符的 txt 文件讀入 java 中的二維數組 將.txt文件中的字符串讀取到並將內容放入二維數組 如何從 .txt 文件中讀取二維數組？ 如何將txt文件讀入2d Array Java 想要讀取.txt文件並將其加載到2D數組中，然后按原樣打印 從 txt.file 中讀取數字並生成二維數組 Txt文件到2D數組
相關標簽
 
粵ICP備18138465號  © 2020-2024 STACKOOM.COM