The Java Tutorials have been written for JDK 8.Java教程是为JDK 8编写的。Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.本页中描述的示例和实践没有利用后续版本中引入的改进，并且可能使用不再可用的技术。See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases.有关Java SE 9及其后续版本中更新的语言特性的摘要，请参阅Java语言更改。
See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.有关所有JDK版本的新功能、增强功能以及已删除或不推荐的选项的信息，请参阅JDK发行说明。
Now we will look at the methods used for importing data into a component. These methods are invoked for the drop gesture, or the paste action, when the component is the target of the operation. The TransferHandler methods for importing data are:
canImport(TransferHandler.TransferSupport) — This method is called repeatedly during a drag gesture and returns true if the area below the cursor can accept the transfer, or false if the transfer will be rejected. For example, if a user drags a color over a component that accepts only text, the canImport method for that component's TransferHandler should return false.
importData(TransferHandler.TransferSupport) — This method is called on a successful drop (or paste) and initiates the transfer of data to the target component. This method returns true if the import was successful and false otherwise.
These methods replace older versions that do not use the TransferSupport class. Unlike its replacement method, canImport(JComponent, DataFlavor[]) is not called continuously.
You will notice that these import methods take a TransferHandler.TransferSupport argument. Next we look at the TransferSupport class and then some sample import methods.