Android SQLite CursorWindowAllocationException崩溃 [英] Android SQLite CursorWindowAllocationException crash

问题描述

当我发出许多cursor.moveToNext（）请求时，我的程序崩溃了。错误消息显示为：

I have a situation where my program crashes when I make a number of cursor.moveToNext() requests. The error message reads:

android.database.CursorWindowAllocationException: Cursor window allocation of 2048 kb failed. # Open Cursors=773 (# cursors opened by this proc=773)
at android.database.CursorWindow.<init>(CursorWindow.java:112)
at android.database.CursorWindow.<init>(CursorWindow.java:100)
at android.database.AbstractWindowedCursor.clearOrCreateWindow(AbstractWindowedCursor.java:198)
at android.database.sqlite.SQLiteCursor.clearOrCreateWindow(SQLiteCursor.java:364)
at android.database.sqlite.SQLiteCursor.fillWindow(SQLiteCursor.java:162)
at android.database.sqlite.SQLiteCursor.getCount(SQLiteCursor.java:156)
at android.database.AbstractCursor.moveToPosition(AbstractCursor.java:161)
at android.database.AbstractCursor.moveToNext(AbstractCursor.java:209)
at net.cunniman.teacherplannerlite.SchoolClassDataSource.getClassForDayView(SchoolClassDataSource.java:173)
at net.cunniman.teacherplannerlite.DayView.getSchoolClasses(DayView.java:200)
at net.cunniman.teacherplannerlite.DayView.displayDate(DayView.java:176)
at net.cunniman.teacherplannerlite.DayView.plusDay(DayView.java:287)
at net.cunniman.teacherplannerlite.DayView.onClick(DayView.java:93)
at android.view.View.performClick(View.java:3565)
at android.view.View$PerformClick.run(View.java:14165)
at android.os.Handler.handleCallback(Handler.java:605)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4514)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:980)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:747)
at dalvik.system.NativeStart.main(Native Method)

try {
this.openForRead();
for (int day_counter = 0; day_counter < DAY_PERIOD.length/2; day_counter++)
{

    Cursor cursor = database.rawQuery
        ("SELECT " + NAME + " FROM " + TABLE_NAME + " WHERE " + DAY_PERIOD[day_counter * 2]
        + " = '" + day + "' AND " + DAY_PERIOD[day_counter * 2 + 1] + " = "
        + Integer.toString(period), null);


while (cursor.moveToNext())
{
    String name = cursor.getString(0);
    sc.setName(name);
}


} finally {
    this.close();
}

有人知道是什么原因吗？-好像是内存泄漏（也许？）但是有办法防止它发生吗？

Does anyone know what might be causing this - seems like a memory leak (maybe?) but is there a way I can prevent it from happening?

谢谢

推荐答案

通常，导致此错误的原因是未关闭的游标。

Most often the cause for this error are non closed cursors. Make sure you close all cursors after using them (even in the case of an error).

Cursor cursor = null;
try {
    cursor = db.query(...
    // do some work with the cursor here. i.e.:
    while (cursor.moveToNext())
    { .... }
} finally {
    // this gets called even if there is an exception somewhere above
    if(cursor != null)
        cursor.close();
}

这篇关于Android SQLite CursorWindowAllocationException崩溃的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！