读取数据库时出现安卓 Java内存不足异常
我试图从数据库中检索数据。然而,在读取时,我的游标抛出了一个Java内存不足异常。查看堆栈跟踪,它与字符串生成器有关。我原以为将代码移动到线程会有效,但我仍然有一个例外。以下是不起作用的代码:
public Object[] getData() {
CustomRunnable runnable = new CustomRunnable();
Thread runThread = new Thread(runnable);
runThread.start();
while ((runThread.getState() != Thread.State.TERMINATED)) {
}
return runnable.getDBlist().toArray();
}
public class CustomRunnable implements Runnable {
List<String> dbList;
public boolean done = false;
@Override
public void run() {
dbList = new ArrayList<>();
SQLiteDatabase sqLiteDatabase = getWritableDatabase();
String query = "SELECT * FROM " + TABLE_ITEMS + " WHERE 1";
//Cursor code
Cursor c = sqLiteDatabase.rawQuery(query, null);
c.moveToFirst();
String dbString = "";
while (!c.isAfterLast()) {
if (c.getString(c.getColumnIndex(COLUMN_ITEMNAME)) != null) {
dbString += c.getString(c.getColumnIndex(COLUMN_ITEMNAME));
}
/*
if(c.getString(c.getColumnIndex(COLUMN_COST))!=null){
dbString+=c.getString(c.getColumnIndex(COLUMN_COST));
}
*/
dbList.add(dbString);
}
c.close();
sqLiteDatabase.close();
done = true;
}
public List<String> getDBlist() {
return dbList;
}
}
这是我的堆栈跟踪:
java.lang.OutOfMemoryError: Failed to allocate a 83410 byte allocation with 71348 free bytes and 69KB until OOM
at java.lang.AbstractStringBuilder.enlargeBuffer(AbstractStringBuilder.java:95)
at java.lang.AbstractStringBuilder.append0(AbstractStringBuilder.java:146)
at java.lang.StringBuilder.append(StringBuilder.java:216)
at com.daita.ereciept.DBHandler.getData(DBHandler.java:62)
at com.daita.ereciept.MainActivity$1.run(MainActivity.java:37)
at java.lang.Thread.run(Thread.java:818)
# 1 楼答案
首先需要解决JVM堆大小问题。如果你确信你没有错
我说的错是。。。你知道引起oom的数据不多。你需要在内存中存储这么多数据