Import the Java. IO. *;
Public class Ex10_4 {
Public static void main (String args []) {
Int n=1;
Byte [] a=new byte [100].
Try {File f=new File (" Ex10_4. Java ");//create a file (source)
InputStream in=new FileInputStream (f);//create a point to file input stream
While ((n=in. Read (a, 0100)).=1) {//not read bytes will return 1
/* loop reads bytes, call int read (byte [], int off, int len),
Read the len bytes in a byte array, starting off to specify from which position */
String s=new String (a, 0, n);
System. The out. Print (s);
}
In the close ();//off flow
}
The catch (Exception e) {
System. The out. Println (" the File read Error "+ e);
}
}
}

Declaration of the variable n=1 don't understand, the while loop and the back of the String (a, 0, n) method is a what
O bosses solve

CodePudding user response:

InputStream of the read () method will stream of bytes read into a byte array, the return value is read to the number of bytes, if return 1, that is not read data,
A, new String (0, n) is the call to a construction method of the String class,
Find a JDK API documentation, see will know that the String class constructor has several,
But if they don't contact me, I have 1.6, 1.7, 1.8 documents, including 1.6 is all in Chinese, 1.7 is all in English, 1.8 half, including the Chinese translation software translation, looking at a little bit difficult

CodePudding user response:

N=1 is useless, because behind n=in. Read (a, 0100) to give n assignment;

A, String (0, n) is the function of the byte array into a String, but the array is not all need to be converted to a String, only need 0 - n bytes,

CodePudding user response:

reference 1/f, three and a half cents response:

InputStream of the read () method will stream of bytes read into a byte array, the return value is read to the number of bytes, if return 1, that is not read data,
A, new String (0, n) is the call to a construction method of the String class,
Find a JDK API documentation, see will know that the String class constructor has several,
But if they don't contact me, I have 1.6, 1.7, 1.8 documents, including 1.6 is all in Chinese, 1.7 is all in English, 1.8 half, including the Chinese translation software translation, looking at a little bit difficult

thank you big brother

CodePudding user response:

refer to the second floor BoRoBoRoMe response:

n=1 is useless, because behind n=in. Read (a, 0100) to give n assignment;

A, String (0, n) is the function of the byte array into a String, but the array is not all need to be converted to a String, only need 0 - n bytes,

n=1 can not

CodePudding user response:

reference 4 floor liujiajia23 response:

Quote: refer to the second floor BoRoBoRoMe response:

n=1 is useless, because behind n=in. Read (a, 0100) to give n assignment;

A, String (0, n) is the function of the byte array into a String, but the array is not all need to be converted to a String, only need 0 - n bytes,

n=1 can I don't

Int n need statement, you can be in the original position statements can also be stated in the while

While ((int n=in the read (a, 0100)).=1)

CodePudding user response:

reference 5 floor qq_39936465 reply:

Quote: refer to 4th floor liujiajia23 response:

Quote: refer to the second floor BoRoBoRoMe response:

n=1 is useless, because behind n=in. Read (a, 0100) to give n assignment;

A, String (0, n) is the function of the byte array into a String, but the array is not all need to be converted to a String, only need 0 - n bytes,

n=1 can I don't

Int n need statement, you can be in the original position statements can also be stated in the while

While ((int n=in the read (a, 0100)).=1)

good thank you