我从String test += str;
中去除了test
,成千上万个字符以指数级增长。花了45分钟才能运行,可能是因为创建了大字符串并删除了垃圾。然后,我将这个输入错开了30秒。StringBuilder在使用java中的大字符串时出现内存不足错误
这似乎是便宜的方式做到这一点,但它运作良好:
if (secondDump.length() > 50)
{
intermedDump = intermedDump + secondDump;
secondDump = "";
}
if (intermedDump.length() > 100)
{
thirdDump = thirdDump + intermedDump;
intermedDump = "";
}
if (thirdDump.length() > 500)
{
fourthDump = fourthDump + thirdDump;
thirdDump = "";
}
if (fourthDump.length() > 1000)
{
fifthDump = fifthDump + fourthDump;
fourthDump = "";
}
//with just this and not sixth. Runtime>>>> : 77343
if (fifthDump.length() > 5000)
{
sixthDump = sixthDump + fifthDump;
fifthDump = "";
}
//with just this. Runtime>>>> : 35903Runtime>>>> : 33780
if (sixthDump.length() > 10000)
{
fillerDump = fillerDump + sixthDump;
sixthDump = "";
}
然后我发现StringBuilder
存在,我一直在尝试使用它,因为,它替换所有的字符串操作。
问题是,我不断收到一个java.lang.OutOfMemoryError
与Java内存堆溢出。我认为这个字符串太长了,无法存储在内存中,因为它使得我之前的代码在内存不足错误崩溃之前所做的大约1/50的进度。它只能在一千字以下的情况下工作。
为什么字符串可以保存整个输出并且不能接近?另外,如果我将文本追加到JTextPane
,那么需要多少内存?如果我将StringBuilder
内容转储到JTextpane
,并且继续追加和清除StringBuilder
,这似乎也不起作用。
这里是现有的代码。网页是正在传递的对象:
protected void concatPlates(page PageA) throws IOException
{
if (backend.isFirstPage == false)
{
frontend.fillOutputPane("\n " +
" \n", PageA);
frontend.fillOutputPane(" " +
" \n", PageA);
frontend.fillOutputPane(" " +
" \n", PageA);
}
for (int i = 0; i < PLATELEN-1; i++)
{
if (arrLeftCol[i].length() == 0)
{
/////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////
frontend.fillOutputPane(arrLeftCol[i].append(
arrRightCol[i]));
}
else
{
PageA.tempStrBuff = new StringBuilder(arrLeftCol[i].substring(0,40));
frontend.fillOutputPane(PageA.tempStrBuff.append(arrRightCol[i]));
}
arrLeftCol[i].append("");
arrRightCol[i].append("");
backend.isFirstPage = false;
}
}
//this is the frontend class
public static void fillOutputPane(String s, page PageA)
{
fillOutputPane(PageA.getStrBuf());
}
public static void fillOutputPane(StringBuilder stringBuild)
{
try
{
str.append(stringBuild);
}
catch (java.lang.OutOfMemoryError e)
{
System.out.println((str.length() * 16) /8);
//System.out.println(str);
System.out.println("out of memory error");
System.exit(0);
}
}
以下是错误:
Exception in thread "AWT-EventQueue-0" java.lang.OutOfMemoryError: Java heap space
at java.util.Arrays.copyOf(Unknown Source)
at java.lang.AbstractStringBuilder.expandCapacity(Unknown Source)
at java.lang.AbstractStringBuilder.append(Unknown Source)
at java.lang.StringBuilder.append(Unknown Source)
at java.lang.StringBuilder.append(Unknown Source)
at backend.fill(backend.java:603)
at frontend$openL.actionPerformed(frontend.java:191)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.AbstractButton.doClick(Unknown Source)
at javax.swing.plaf.basic.BasicMenuItemUI.doClick(Unknown Source)
at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$000(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
我觉得这是一个堆栈跟踪是什么:
java.lang.Exception: Stack trace
at java.lang.Thread.dumpStack(Unknown Source)
at frontend.fillOutputPane(frontend.java:385)
at page.concatPlates(page.java:105)
at backend.setPlate(backend.java:77)
at backend.fill(backend.java:257)
at frontend$openL.actionPerformed(frontend.java:191)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.AbstractButton.doClick(Unknown Source)
at javax.swing.plaf.basic.BasicMenuItemUI.doClick(Unknown Source)
at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$000(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$2.run(Unknown Source)
at java.awt.EventQueue$2.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)81240560
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
什么是虚拟机参数?尝试增加堆大小。 – Viruzzo
您可以在您使用StringBuilder类的地方添加代码。错误更可能在那里。 – JustinKSU
更多细节将有所帮助。我怀疑内存中的字符串会导致内存不足。你有堆栈跟踪吗? –