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

我试图使用System.out.print打印数组的内容，但遇到以下错误：

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 + "    ");
    }
}

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我没有任何调试器经验，因此非常感谢您的帮助，谢谢。

我想您引用的索引是错误的

将itemList.getj更改为itemList.getq

如果j是项目列表的大小，itemList.getj将给您一个超出范围的索引，因为从零开始的索引只会指向j-1。看起来您希望从代码中获得itemList.getq。

这是一个错误！ 使用：

如Renjith所说，更改为.getj，您还可以确保永远不会出现您所处的情况

而不是

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

做

这样你就无法从大于列表/数组大小的任何内容中获取。这似乎是一个非常常见的错误。如果您使用的任何IDE都像伊柯丽斯，则应该考虑更多地了解调试透视图。

< P>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

原因是您在列表中迭代查找值为list size的列表

---

当循环索引总是

 itemList.get(j).selectedType

你需要用这个

 itemList.get(q).selectedType

---

您确定不应该使用getq吗？谢谢，所有解决方案都有效。谢谢，所有解决方案都有效。谢谢，所有解决方案都有效。我更喜欢这一款，因为它坚固耐用。

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

 itemList.get(j).selectedType

 itemList.get(q).selectedType