PipedInputStream类的available()方法 (PipedInputStream Class available() method)

• available() method is available in java.io package.

  available()方法在java.io包中可用。

• available() method is used to return the number of available bytes left that can be read from this PipedInputStream without blocking.

  available()方法用于返回可以从此PipedInputStream读取而不会阻塞的剩余可用字节数。

• available() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  available()方法是一种非静态方法，只能通过类对象访问，如果尝试使用类名称访问该方法，则会收到错误消息。

• available() method may throw an exception at the time of returning the available bytes left.

  在返回剩余的可用字节时， available()方法可能会引发异常。

  IOException: This exception may throw when getting any input/output error while performing.

  IOException ：在执行过程中遇到任何输入/输出错误时，可能引发此异常。

Syntax:

句法：

    public int available();

Parameter(s):

参数：

• It does not accept any parameter.

  它不接受任何参数。

Return value:

返回值：

The return type of the method is int, it returns the number of available bytes that can be read without blocking as it may return 0 when this stream closed by using the close() method.

方法的返回类型为int ，它返回可以读取而不会阻塞的可用字节数，因为当使用close()方法关闭此流时，它可能返回0。

Example:

例：

// Java program to demonstrate the example 
// of int available() method 
// of PipedInputStream
import java.io.*;
public class AvailableOfPIS {
public static void main(String[] args) throws Exception {
int val = 65;
try {
// Instantiates PipedInputStream and 
// PipedOutputStream
PipedInputStream pipe_in = new PipedInputStream();
PipedOutputStream pipe_out = new PipedOutputStream();
// By using connect() method is to connect
// this pipe_in to the given pipe_out
pipe_in.connect(pipe_out);
for (int i = 0; i < 3; ++i) {
// By using write() method is to
// write the val to the stream pipe_out
pipe_out.write(val);
val++;
}
// By using available() method is to return
// the available bytes to be read
int avail_bytes = pipe_in.available();
System.out.println("pipe_in.available(): " + avail_bytes);
for (int i = 0; i < 3; ++i) {
// By using read() method is to
// read the integer and convert it into
// char
char ch = (char) pipe_in.read();
System.out.println("pipe_in.read(): " + ch);
}
// By using close() method is to close
// the stream
pipe_in.close();
pipe_out.close();
} catch (Exception ex) {
System.out.println(ex.toString());
}
}
}

Output

输出量

pipe_in.available(): 3
pipe_in.read(): A
pipe_in.read(): B
pipe_in.read(): C

翻译自: https://www.includehelp.com/java/pipedinputstream-available-method-with-example.aspx