readLine
method for reading data one lineServletInputStream
object can be used to read data sent from the
* A ServletInputStream
object is normally retrieved via the
* {@link ServletRequest#getInputStream} method.
*
* This is an abstract class that a servlet container implements. Subclasses of
* this class must implement the java.io.InputStream.read()
method.
*
* @see ServletRequest
*/
public abstract class ServletInputStream extends InputStream {
/**
* Does nothing, because this is an abstract class.
*/
protected ServletInputStream() {
// NOOP
}
/**
* Reads the input stream, one line at a time. Starting at an offset, reads
* bytes into an array, until it reads a certain number of bytes or reaches
* a newline character, which it reads into the array as well.
*
* This method returns -1 if it reaches the end of the input stream before
* reading the maximum number of bytes.
*
* @param b
* an array of bytes into which data is read
* @param off
* an integer specifying the character at which this method
* begins reading
* @param len
* an integer specifying the maximum number of bytes to read
* @return an integer specifying the actual number of bytes read, or -1 if
* the end of the stream is reached
* @exception IOException
* if an input or output exception has occurred
*/
public int readLine(byte[] b, int off, int len) throws IOException {
if (len <= 0) {
return 0;
}
int count = 0, c;
while ((c = read()) != -1) {
b[off++] = (byte) c;
count++;
if (c == '\n' || count == len) {
break;
}
}
return count > 0 ? count : -1;
}
/**
* Returns true
if all the data has been read from the stream,
* else false
.
*
* @since Servlet 3.1
*/
public abstract boolean isFinished();
/**
* Returns true
if data can be read without blocking, else
* false
. If this method is called and returns false, the
* container will invoke {@link ReadListener#onDataAvailable()} when data is
* available.
*
* @since Servlet 3.1
*/
public abstract boolean isReady();
/**
* Sets the {@link ReadListener} for this {@link ServletInputStream} and
* thereby switches to non-blocking IO. It is only valid to switch to
* non-blocking IO within async processing or HTTP upgrade processing.
*
* @param listener The non-blocking IO read listener
*
* @throws IllegalStateException If this method is called if neither
* async nor HTTP upgrade is in progress or
* if the {@link ReadListener} has already
* been set
* @throws NullPointerException If listener is null
*
* @since Servlet 3.1
*/
public abstract void setReadListener(ReadListener listener);
}
以上这篇浅谈request.getinputstream只能读取一次的问题就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持中文源码网。
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