Question

我正在尝试使用System.out.print（）打印数组的内容但是我遇到了这个错误：

Exception in thread "AWT-EventQueue-0" java.lang.IndexOutOfBoundsException: Index: 2, Size: 2
at java.util.ArrayList.rangeCheck(ArrayList.java:604)
at java.util.ArrayList.get(ArrayList.java:382)
at Polymorphism.actionPerformed(Polymorphism.java:196)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6505)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6270)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4861)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Window.dispatchEventImpl(Window.java:2713)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:707)
at java.awt.EventQueue.access$000(EventQueue.java:101)
at java.awt.EventQueue$3.run(EventQueue.java:666)
at java.awt.EventQueue$3.run(EventQueue.java:664)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:680)
at java.awt.EventQueue$4.run(EventQueue.java:678)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:677)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

错误所指的行是第3行：

 else if (e.getSource() == printArray) {
        for (int q=0; q<j; q++){
            System.out.print("Type: " + itemList.get(j).selectedType + "    ");
            System.out.print("Width: " + itemList.get(j).selectedWidth + "    ");
            System.out.print("Length: " + itemList.get(j).selectedLength + "    ");
    }
}

我没有任何调试器经验，所以感谢您的帮助，谢谢。

Answer 1

改为 .get（j），正如Renjith所说，你也可以确保永远不会在你所处的情况下结束

而不是

for (int q=0; q<j; q++) {

DO

for (int q=0; q<itemList.size(); q++) {

这样你就不能从任何大于列表/数组

的大小.get

Answer 2

我指的是错误的索引。

将itemList.get（j）更改为itemList.get（q）;

Answer 3

这是一个大错！使用：

else if (e.getSource() == printArray) {
        for (int q=0; q<j; q++){
            System.out.print("Type: " + itemList.get(q).selectedType + "    ");
            System.out.print("Width: " + itemList.get(q).selectedWidth + "    ");
            System.out.print("Length: " + itemList.get(q).selectedLength + "    ");
    }
}

Answer 4

替换

        System.out.print("Type: " + itemList.get(j).selectedType + "    ");
        System.out.print("Width: " + itemList.get(j).selectedWidth + "    ");
        System.out.print("Length: " + itemList.get(j).selectedLength + "    ");

与

   System.out.print("Type: " + itemList.get(q).selectedType + "    ");
   System.out.print("Width: " + itemList.get(q).selectedWidth + "    ");
   System.out.print("Length: " + itemList.get(q).selectedLength + "    ");

原因是你正在使用列表大小的查找值迭代列表。

当循环索引（总是＆lt; listsize）大于listsize（在这种情况下为2）时，条件正在破坏

Answer 5

如果j是项目列表的大小，itemList.get(j)将为您提供超出范围的索引，因为从零开始的索引只会转到j - 1。它看起来像您希望itemList.get(q)来自您的代码。

Answer 6

您正在使用此代码打印元素

 itemList.get(j).selectedType

你需要使用这个

 itemList.get(q).selectedType

Answer 7

这似乎是pretty common mistake。如果您使用任何IDE like Eclipse，则应考虑详细了解Debug Perspective。

Java：打印数组：IndexOutOfBoundsException：索引：2，大小：2

7 个答案: