java.lang.NumberFormatException: Invalid int: "null"

Question

提问by ana ana

The method getAllActivities() must return all activities from database in array list format But I got: java.lang.NumberFormatException: Invalid int: "null", at activity.setActivityType(Integer.parseInt(cursor.getString(1)));I don't know what is wrong

方法 getAllActivities() 必须以数组列表格式返回数据库中的所有活动但我得到了：java.lang.NumberFormatException: Invalid int: "null", at activity.setActivityType(Integer.parseInt(cursor.getString(1)));I don't know what is wrong

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteStatement;
import com.yast.util.Constants;
import com.yast.util.Utils;
import java.util.ArrayList;
import java.util.List;


public class DatabaseHandler extends SQLiteOpenHelper {
    private static final int DATABASE_VERSION = 1;
    private static final String DATABASE_NAME = "YastDB.db";

    // Activities table name
    private static final String TABLE_ACTIVITIES = "Activities";

    // Activities Table Columns names
    private static final String KEY_ID = "id";
    private static final String KEY_ACTIVITYTYPE = "ActivityType";
    private static final String KEY_HARTRATE = "HartRate";
    private static final String KEY_HARTBATNO = "HartBatNo";
    private static final String KEY_DISTANCE = "Distance";
    private static final String KEY_SPEED = "Speed";
    private static final String KEY_STRIDES = "Strides";
    private static final String KEY_STARTDATETIME = "StartDateTime";
    private static final String KEY_ENDDATETIME = "EndDateTime";
    public static final String  KEY_CURRENTDATETIME = "CurrentDateTime";

    private String[] PROJECTION = new String[]{ KEY_ID,
            KEY_ACTIVITYTYPE, KEY_HARTRATE,KEY_HARTBATNO, KEY_DISTANCE,
            KEY_SPEED,KEY_STRIDES,KEY_STARTDATETIME,KEY_ENDDATETIME
            ,KEY_CURRENTDATETIME};

    public DatabaseHandler(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    // Creating Tables
    @Override
    public void onCreate(SQLiteDatabase db) {
        String CREATE_Activitys_TABLE = "CREATE TABLE " + TABLE_ACTIVITIES + "("
                + KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
                KEY_ACTIVITYTYPE + " INTEGER,"+
                KEY_HARTRATE + " INTEGER, "+
                KEY_HARTBATNO + " INTEGER,"+
                KEY_DISTANCE + " INTEGER," +
                KEY_SPEED + " INTEGER," +
                KEY_STRIDES + " INTEGER," +
                KEY_STARTDATETIME + " TEXT," +
                KEY_ENDDATETIME + " TEXT," +
                KEY_CURRENTDATETIME + " TEXT" +
                ")";
        db.execSQL(CREATE_Activitys_TABLE);
    }

    // Upgrading database
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // Drop older table if existed
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_ACTIVITIES);

        // Create tables again
        onCreate(db);
    }

    //CRUD operations (Create, Read, Update and Delete)
    // Adding new activity
    public void addActivity(ActivityEntity activity) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(KEY_ACTIVITYTYPE, activity.getActivityType()); // Activity type
        values.put(KEY_HARTRATE, activity.getHartRate());
        values.put(KEY_HARTBATNO, activity.getHartBatNo());
        values.put(KEY_DISTANCE, activity.getDistance());
        values.put(KEY_SPEED, activity.getSpeed());
        values.put(KEY_STRIDES, activity.getStrides());
        values.put(KEY_STARTDATETIME,activity.getStartDateTime().toString());
        values.put(KEY_ENDDATETIME, activity.getEndDateTime().toString());
        values.put(KEY_CURRENTDATETIME, activity.getCurrentDateTime().toString());

        // Inserting Row
        db.insert(TABLE_ACTIVITIES, null, values);
        db.close(); // Closing database connection

    }

    // Getting single Activity
    /*
    The following method getActivity() will read single contact row.
    It accepts id as parameter and will return the matched row from the database.
     */
    public ActivityEntity getActivity(int id) {
        ActivityEntity activity = null;
        SQLiteDatabase db = this.getReadableDatabase();

        String where = KEY_ID + "=?";
        String[] selectionArg = new String[]{String.valueOf(id)};

        Cursor cursor = db.query(TABLE_ACTIVITIES, PROJECTION, where, selectionArg,
 null, null, null, null);
        if (cursor != null) {
            cursor.moveToFirst();

            activity = new ActivityEntity(Integer.parseInt(cursor.getString(0)),
                    Integer.parseInt(cursor.getString(1)),
                    Integer.parseInt(cursor.getString(2)),
                    Integer.parseInt(cursor.getString(3)),
                    Integer.parseInt(cursor.getString(4)),
                    Integer.parseInt(cursor.getString(5)),
                    Integer.parseInt(cursor.getString(6)),
                    cursor.getString(7),
                    cursor.getString(8),
                    cursor.getString(9));
        }
        return activity;
    }

    // Getting All Activities
    public ArrayList<ActivityEntity> getAllActivitys() {

        ArrayList<ActivityEntity> activitiesList = new ArrayList<ActivityEntity>();
        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.query(TABLE_ACTIVITIES, PROJECTION, null, null, null, null, null, null);

        // looping through all rows and adding to list
        if (cursor.moveToFirst()) {
            do {
                ActivityEntity activity = new ActivityEntity();
                activity.setID(Integer.parseInt(cursor.getString(0)));
                activity.setActivityType(Integer.parseInt(cursor.getString(1)));
                activity.setHartRate(Integer.parseInt(cursor.getString(2)));
                activity.setHartBatNo(Integer.parseInt(cursor.getString(3)));
                activity.setDistance(Integer.parseInt(cursor.getString(4)));
                activity.setSpeed(Integer.parseInt(cursor.getString(5)));
                activity.setStrides(Integer.parseInt(cursor.getString(6)));
                activity.setStartDateTime(cursor.getString(7));
                activity.setEndDateTime(cursor.getString(8));
                activity.set_currentDateTime(cursor.getString(9));

                // Adding activity to list
                activitiesList.add(activity);
            } while (cursor.moveToNext());

        }
        return activitiesList;
    }


    public int getActivitiesCount() {

        String countQuery = "SELECT  * FROM " + TABLE_ACTIVITIES;
        SQLiteDatabase db = this.getReadableDatabase();
        Cursor cursor = db.rawQuery(countQuery, null);
        cursor.close();

        // return count
        return cursor.getCount();
    }

    // Updating single Activity
    public int updateActivity(ActivityEntity activity) {
            SQLiteDatabase db = this.getWritableDatabase();

            String where = KEY_ID + "=?";

            ContentValues values = new ContentValues();
            values.put(PROJECTION[1], activity.getActivityType());
            values.put(PROJECTION[2], activity.getHartRate());
            values.put(PROJECTION[3], activity.getHartBatNo());
            values.put(PROJECTION[4], activity.getDistance());
            values.put(PROJECTION[5], activity.getSpeed());
            values.put(PROJECTION[6], activity.getStrides());
            values.put(PROJECTION[7], activity.getStartDateTime().toString());
            values.put(PROJECTION[8], activity.getEndDateTime().toString());
            values.put(PROJECTION[9], activity.getCurrentDateTime().toString());


            // updating row
            return db.update(TABLE_ACTIVITIES, values, where, new String[] { String.valueOf(activity.getID()) });
    }

    public void deleteActivity(ActivityEntity activity)
    {
        String where = KEY_ID + "=?";

        SQLiteDatabase db = this.getWritableDatabase();
        db.delete(TABLE_ACTIVITIES, where,
                new String[] { String.valueOf(activity.getID()) });
        db.close();
    }

    public void bulkInsert(ArrayList<ActivityEntity> arrayOfActivities) {
        SQLiteDatabase db = this.getWritableDatabase();
        String sql = "INSERT INTO "+ TABLE_ACTIVITIES +" VALUES (?,?,?,?,?,?,?,?,?,?);";
        SQLiteStatement statement = db.compileStatement(sql);
        db.beginTransaction();
       for (ActivityEntity a : arrayOfActivities ) {
            statement.clearBindings();
            statement.bindLong(1, (long) a.getID());
            statement.bindLong(2, (long) a.getActivityType());
            statement.bindLong(3, (long) a.getHartRate());
            statement.bindLong(4, (long) a.getHartBatNo());
            statement.bindLong(5, (long) a.getDistance());
            statement.bindLong(6, (long) a.getSpeed());
            statement.bindLong(7, (long) a.getStrides());
            statement.bindString(8, a.getStartDateTime());
            statement.bindString(9, a.getEndDateTime());
            statement.bindString(10,a.getCurrentDateTime());

            statement.clearBindings();
            statement.execute();
        }
        db.setTransactionSuccessful();
        db.endTransaction();
    }


}

ActivityEntity.java calss:

ActivityEntity.java 类：

import com.yast.util.Constants;
import com.yast.util.Utils;
import java.util.Date;

public class ActivityEntity {

    int id;
    int activityType;
    int hartRate;
    int hartBatNo;
    int distance;
    int speed;
    int strides;
    String startDateTime;
    String endDateTime;
    String currentDateTime;

    public ActivityEntity(){

    }
    // constructor
    public ActivityEntity(int Id, int activityType, int hartRate, int _hartBatNo, int distance, int speed, int strides, String startDateTime, String endDateTime, String currentDateTime){
        this.id = Id;
        this.activityType = activityType;
        this.hartRate = hartRate;
        this.hartBatNo = _hartBatNo;
        this.distance = distance;
        this.speed = speed;
        this.strides = strides;
        this.startDateTime = startDateTime;
        this.endDateTime = endDateTime;
        this.currentDateTime = currentDateTime;
    }
    public void setID(int id){
        this.id = id;
    }
    public int getID(){
        return this.id;
    }
    public void setActivityType(int activityType){
        this.activityType = activityType;
    }
    public int getActivityType(){
        return this.activityType;
    }
    public void setHartRate(int hartRate){
        this.hartRate = hartRate;
    }

    public int getHartRate(){
        return this.hartRate;
    }
    public void setHartBatNo(int hartBatNo){
        this.hartBatNo = hartBatNo;
    }
    public int getHartBatNo(){
        return this.hartBatNo;
    }

    public void setDistance(int distance){
        this.distance = distance;
    }

    public int getDistance(){
        return this.distance;
    }

    public void setSpeed(int speed){
        this.speed = speed;
    }

    public int getSpeed(){
        return this.speed;
    }

    public void setStrides(int strides){
        this.strides = strides;
    }

    public int getStrides(){
        return this.strides;
    }

    public void setStartDateTime(String startDateTime){
        this.startDateTime = startDateTime;
    }

    public String getStartDateTime(){
        return this.startDateTime;
    }

    public void setEndDateTime(String endDateTime){
        this.endDateTime = endDateTime;
    }

    public String getEndDateTime(){
        return this.endDateTime;
    }

    public void set_currentDateTime(String currentDateTime){
        this.currentDateTime = currentDateTime;
    }
    public String getCurrentDateTime(){
        return this.currentDateTime;
    }

    @Override
    public String toString() {
        return "ActivityEntity{" +
                "id=" + id +
                ", activityType=" + activityType +
                ", hartRate=" + hartRate +
                ", hartBatNo=" + hartBatNo +
                ", distance=" + distance +
                ", speed=" + speed +
                ", strides=" + strides +
                ", startDateTime='" + startDateTime + '\'' +
                ", endDateTime='" + endDateTime + '\'' +
                ", currentDateTime='" + currentDateTime + '\'' +
                '}';
    }
}

Answer 1

采纳答案by Ankit Lamba

in your code, if cursor.getString(int num)returns null, then Integer.parseInt(String str)will throw NumberFormatException.

在您的代码中，如果cursor.getString(int num)返回null，Integer.parseInt(String str)则将抛出NumberFormatException。

To avoid this, you should have check for what the cursor.getString(int num)returns.

为避免这种情况，您应该检查cursor.getString(int num)返回的内容。

OR, you can use try-catchand print the appropriate message in catchif you'll get NumberFormatException.

或者，您可以使用try-catch并打印相应的报文catch，如果你会得到NumberFormatException。

Answer 2

回答by Dave Newton

"null"isn't a valid int. Check for null first.

"null"不是有效的 int。首先检查是否为空。

Answer 3

回答by M D

You should check your cursorvalue is nullor not.

你应该检查你的cursor价值是null与否。

if(cursor.isNull(column))
{
//Value is null
}else{

return cursor.getString(column);

}

Answer 4

回答by Bathsheba

You need to be more careful checking for nullness:

您需要更仔细地检查空值：

1) cursoritself could be null

1）cursor本身可能是null

2) cursor.getString(1)could be null

2）cursor.getString(1)可能是null

Putting this together:

把这个放在一起：

if (cursor != null && cursor.getString(1) != null){
    /*your parse will be safe here*/
}

Note that I'm exploiting the fact that an ifwill evaluate from left to right and will stop evaluation once the result is known.

请注意，我正在利用这样一个事实，即 anif将从左到右进行评估，并且一旦知道结果就会停止评估。

As an optimisation, you might want to store the result of cursor.getString(1)to prevent your having to evaluate this twice. But get the code working first.

作为优化，您可能希望存储的结果，cursor.getString(1)以防止您必须对它进行两次评估。但首先让代码工作。

Answer 5

回答by Natraj

activity.setActivityType(Integer.parseInt(cursor.getString(1)));

in this cursor.getString(1)is getting null and That is why you are getting nullpointer exception. Check for that String value.

在这cursor.getString(1)得到空值，这就是为什么你得到空指针异常。检查该字符串值。

Answer 6

回答by krodmannix

Cursor cursor = db.query(TABLE_ACTIVITIES, PROJECTION, null, null, null, null, null, null);

Your SQL query string, the first null input in the query method, is null. You have not provided a query. I am assuming you want all columns from the table, so perhaps fill the query like:

您的 SQL 查询字符串（查询方法中的第一个空输入）为空。您尚未提供查询。我假设您想要表中的所有列，因此可以像这样填写查询：

String SQLSTATEMENT = "SELECT " + KEY_ID + "," + KEY_ACTIVITYTYPE + "," KEY_HARTRATE + "," KEY_HARTBATNO + "," KEY_DISTANCE + "," KEY_SPEED,KEY_STRIDES + "," KEY_STARTDATETIME + "," KEY_ENDDATETIM + "," KEY_CURRENTDATETIME;

Cursor cursor = db.query(TABLE_ACTIVITIES, PROJECTION, SQLSTATEMENT, null, null, null, null, null);

Answer 7

回答by user3091530

Before you convert the value to Integer, you have to check whether the value is integer or not. If it is not an integer then replace it to default integer.

在将值转换为 Integer 之前，您必须检查该值是否为 integer。如果它不是整数，则将其替换为默认整数。

activity.setActivityType(Integer.parseInt(nulltoIntegerDefalt(cursor.getString(1))));
activity.setActivityType(Integer.parseInt(nulltoIntegerDefalt(cursor.getString(1))));
activity.setHartRate(Integer.parseInt(nulltoIntegerDefalt(cursor.getString(2))));
activity.setHartBatNo(Integer.parseInt(nulltoIntegerDefalt(cursor.getString(3))));
activity.setDistance(Integer.parseInt(nulltoIntegerDefalt(cursor.getString(4))));
activity.setSpeed(Integer.parseInt(nulltoIntegerDefalt(cursor.getString(5))));
activity.setStrides(Integer.parseInt(nulltoIntegerDefalt(cursor.getString(6))));

 String nulltoIntegerDefalt(String value){
    if(!isIntValue(value)) value="0";
    return value;

}

boolean isIntValue(String val)
{
    try {
        val=val.replace(" ","");
        Integer.parseInt(val);
    } catch (Exception e) {return false;}
    return true;
}

Answer 8

回答by Nicoolasens

The problem should be solved now, so I'm just solving the exception

问题现在应该解决了，所以我只是在解决异常

An easier way is to change if(){}else{}" by "try{}catch(Exception e){}

更简单的方法是改变 if(){}else{}" by "try{}catch(Exception e){}

Example :

例子：

try { 
//Avoid/éviter (FATAL EXCEPTION: main java.lang.NumberFormatException: Invalid int: "")

//exemple / Exemple d'action

    int userWeight = Integer.parseInteger(userData);
    Intent intent = new Intent(MainActivity.this, SecondActivity.class);
    intent.putExtra("weight", userWeight);  

//                control Toast/Toast de contr?le
    Toast.makeText(MainActivity.this, "OK", Toast.LENGTH_LONG).show();

}
catch (Exception e) {
    Toast.makeText(MainActivity.this, "not OK", Toast.LENGTH_LONG).show();
}

Answer 9

回答by Behzad

Thanks to @user3091530 answer. I have used my own ParsInt method. Create a class named Math.

感谢@user3091530 的回答。我使用了我自己的 ParsInt 方法。创建一个名为 Math 的类。

public class Math {

    //Checking the value if null return zero
    public int ParsIntOrDefalt(String value){
        return Integer.parseInt(NullIntegerDefalt(value));
    }

    private String NullIntegerDefalt(String value) {
        if (!isIntValue(value)) value = "0";
        return value;
    }

    private boolean isIntValue(String val){
        try {
            val=val.replace(" ","");
            Integer.parseInt(val);
        } catch (Exception e) {return false;}
        return true;
    }
}

So, we can use it instead of the main Integer.parseInt() method:

因此，我们可以使用它代替主要的 Integer.parseInt() 方法：

Math math = new Math();
activity.setActivityType(math.ParsIntOrDefalt(cursor.getString(1)));

java.lang.NumberFormatException: Invalid int: "null"

提问by ana ana

采纳答案by Ankit Lamba

回答by Dave Newton

回答by M D

回答by Bathsheba

回答by Natraj

回答by krodmannix

回答by user3091530

回答by Nicoolasens

回答by Behzad

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标签

java.lang.NumberFormatException: Invalid int: "null"

提问by ana ana

采纳答案by Ankit Lamba

回答by Dave Newton

回答by M D

回答by Bathsheba

回答by Natraj

回答by krodmannix

回答by user3091530

回答by Nicoolasens

回答by Behzad

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