java.io.writer的append和write方法有什么区别？
java.io.Writer 接口有两个方法，称为append和write 。这两者有什么区别？它甚至说
以
完全相同out.append(c)形式调用此方法的行为与调用out.write(c)
所以有什么原因两个方法名称变体？
The java.io.Writer interface has two methods called append and write. What are the differences between these two? It even says that
An invocation of this method of the form
out.append(c)behaves in exactly the same way as the invocationout.write(c)
so what is the reason for having two method name variants?
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append() 和 write() 之间存在细微差别。所有这些您都可以通过阅读 Javadocs 来解决。暗示。 ;)
voidwrite 是在 CharSequence 可用之前创建的较旧样式格式。
这些方法被重载，因此有一个
write(int)，其中int被强制转换为 char。append(char)必须是 char 类型。write(char[] chars)接受一个 char 数组，没有等效的append()。There are minor differences between append() and write(). All of which you can work out by reading the Javadocs. Hint. ;)
voidwrite is an older style format created before CharSequence was available.
These methods are overloaded so that there is a
write(int)where theintis cast to a char.append(char)must be a char type.write(char[] chars)takes an array of char, there is no equivalent append().可能是为了符合Appendable接口： http://download .oracle.com/javase/6/docs/api/java/lang/Appendable.html
Probably to conform to the Appendable interface: http://download.oracle.com/javase/6/docs/api/java/lang/Appendable.html
Append()可以采用CharSequence，而write()则采用String。由于
String是CharSequence的实现，因此您还可以将String传递给append()。但您也可以将StringBuilder或StringBuffer传递给append，这是write()无法做到的。Append()can take aCharSequence, whereaswrite()takes aString.Since
Stringis an implementation ofCharSequence, you can also pass aStringtoappend(). But you can also pass aStringBuilderorStringBuffertoappend, which you can't do withwrite().从文档中可以看出，append 还会返回您刚刚写入的 Writer，以便您可以执行多个追加，例如：
As you can see from the documentation, append also returns the Writer you have just written to so that you can perform multiple appends such as:
Writer.append(c)返回 Writer 实例。因此，您可以链接多个附加调用，例如out.append("Hello").append("World");Writer.append(c)returns the Writer instance. Thus you can chain multiple calls to append, e.g.out.append("Hello").append("World");在我看来，它是
Appendable接口的副产品，java.io.Writer实现该接口是为了提供与java.util.Formatter的兼容性。正如您所指出的，文档指出，对于 java.io.Writer，这两种方法之间没有实际区别。Looks to me like it's a byproduct of the
Appendableinterface whichjava.io.Writerimplements in order to provide compatibility withjava.util.Formatter. As you noted, the documentation points out that forjava.io.Writerthere is no practical difference between the two methods.上面所指出的是真实的。
BufferWiter的append()方法的不同风格返回一个Writer，它实现了Appendable等，从而使您能够链式调用。此外，append()允许您传递CharSequence以及char，而不是int>、String或char[]，与write()方法一样。全部正确。然而，正如问题所述，需要指出的一个重要问题是
append()的底层行为仍然与write()的基本行为相同。尽管有些误导性的命名法，现有的文件内容将被覆盖，不附加，除非您的FileWriter被实例化：从这个意义上说，我认为最初的问题提出了一个有效的观点。
What has been noted above is true. The different flavours of
BufferWiter'sappend()method return aWriter, which implementsAppendable, among others, thereby affording you the ability to chain calls. In addition,append()allows you to pass aCharSequenceas well as achar, as opposed to anint,Stringorchar[], as with thewrite()methods. All correct.However, as the question states, an important issue to point out that the underlying behaviour of
append()is still much the same as that ofwrite(). Despite the somewhat misleading nomenclature, existing file content will be overwritten, not appended, unless yourFileWriteris instantiated otherwise:In that sense I think the original question raises a valid point.