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BufferedWriter里的write（）

BufferedWriter里的write（）# Java - 爪哇娇娃

c*n2006-02-19 08:02

1 楼

write
public void write(int c)
throws IOException
Write a single character.
Overrides:
write in class Writer
Throws:
IOException - If an I/O error occurs
这里说的是write a single character,但怎么输入参数却是int呢？
比如我要写一个字符 'c'到这个 BufferedWriter bw里面去，怎么写呢？
bw.write('c')就可以了么？

g*g2006-02-19 08:02

2 楼

char can be casted to int, I think it should work.

【在 c*********n 的大作中提到】

: write
: public void write(int c)
: throws IOException
: Write a single character.
: Overrides:
: write in class Writer
: Throws:
: IOException - If an I/O error occurs
: 这里说的是write a single character,但怎么输入参数却是int呢？
: 比如我要写一个字符 'c'到这个 BufferedWriter bw里面去，怎么写呢？

c*n2006-02-19 08:02

3 楼

我觉得逻辑应该是反过来的， + 运算符只对String类型重载
好比method的重载
已经有了
methodName(int parameter)
现在重新写一个
methodName(String strParameter)

Well that's what it's special about - String is the only class that supports
overloading +.

g*g2006-02-19 08:02

4 楼

char->short->int->double, you don't need to cast in
that direction.

【在 c*********n 的大作中提到】

: 我觉得逻辑应该是反过来的， + 运算符只对String类型重载
: 好比method的重载
: 已经有了
: methodName(int parameter)
: 现在重新写一个
: methodName(String strParameter)
:
: Well that's what it's special about - String is the only class that supports
: overloading +.

c*n2006-02-19 08:02

5 楼

我已经试过了，这个的确是可以的
但java不是号称是严格检查数据类型的语言么？
难道这里也可以像c语言一样自动转换类型而不需要在c前面加上(int)？

char can be casted to int, I think it should work.

【在 g*****g 的大作中提到】

: char can be casted to int, I think it should work.

c*n2006-02-19 08:02

6 楼

p*p2006-02-19 08:02

7 楼

Primitive Type is not object
but string is special object, is it right_

【在 c*********n 的大作中提到】

r*n2006-02-19 08:02

8 楼

String is not primitive type. String extends from Object. String is immutable,
which makes String "special".

【在 p***p 的大作中提到】

: Primitive Type is not object
: but string is special object, is it right_

m*t2006-02-19 08:02

9 楼

Well that's what it's special about - String is the only class that supports
overloading +.

【在 c*********n 的大作中提到】

m*t2006-02-19 08:02

10 楼

Good point, too.

【在 g*****g 的大作中提到】

: char->short->int->double, you don't need to cast in
: that direction.

c*t2006-02-19 08:02

11 楼

The reason is actually because all string literals are stored in a
hash table in class file. So duplicate strings are eliminated in the
compiled class file.
There are some horrible programmers at Sun that does things like
variable == "Center"
in the code. Maybe they knew it better, but still it is a bad
approach.

【在 g*****g 的大作中提到】

: char->short->int->double, you don't need to cast in
: that direction.

c*n2006-02-19 08:02

12 楼

char->short?
or
byte->short?

char->short->int->double, you don't need to cast in
that direction.

【在 g*****g 的大作中提到】

: char->short->int->double, you don't need to cast in
: that direction.

m*t2006-02-19 08:02

13 楼

Good question. I have always wondered why, too.

【在 c*********n 的大作中提到】

: char->short?
: or
: byte->short?
:
: char->short->int->double, you don't need to cast in
: that direction.

m*t2006-02-19 08:02

14 楼

Right, that's what's special about String. I don't see any material difference
in what we are saying, man. 8-)

【在 c*********n 的大作中提到】

c*n2006-02-19 08:02

15 楼

thanks!

http://www.particle.kth.se/~lindsey/JavaCourse/Book/Part1/Java/Chapter02/castsMixing.html

【在 g*****g 的大作中提到】

: char->short->int->double, you don't need to cast in
: that direction.

m*t2006-02-19 08:02

16 楼

immutable,
Hmm, I'm not sure about that - many classes are immutable. I think String is
special because it's the only non-primitive type that supports operator +, and
the compiler does some special optimization supporting that.

【在 r****n 的大作中提到】

: String is not primitive type. String extends from Object. String is immutable,
: which makes String "special".