Java Scanner NoSuchElementException
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Scanner scan = new Scanner(System.in);
scan.next();
scan.close();
scan = new Scanner(System.in);
scan.next();
µ±³ÌÐòÔËÐе½µÚÎåÐÐÊÇ»áÅ׳öjava.util.NoSuchElementException
at java.util.Scanner.throwFor(Scanner.java:838)
at java.util.Scanner.next(Scanner.java:1347)
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StreamDecoder ʵÀý sd
private final StreamDecoder sd;
¶øscan.close()·½·¨Îª
public void close() {
if (closed)
return;
if (source instanceof Closeable) {
try {
((Closeable)source).close();
} catch (IOException ioe) {
lastException = ioe;
}
}
sourceClosed = true;
source = null;
closed = true;
}
µ±Ö´Ðе½ ((Closeable)source).close();¾Í»á½øÈëInputStreamReaderµÄclose()·½·¨£º
public void close() throws IOException {
sd.close();
}
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µ±Ö´ÐÐÈç´íÎó²úÉú´úÂëµÄµÚ5ÐдúÂë scan.next()ʱ£¬
public String next() {
ensureOpen();
clearCaches();
while (true) {
String token = getCompleteTokenInBuffer(null);
if (token != null) {
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publicd class syncTest {
…
synchronized void aMethod() {
//ÐèҪͬ²½Ê¹ÓõĴúÂë
}
}
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import java.awt.Color;
import java.io.FileOutputStream;
import com.lowagie.text.Cell;
import com.lowagie.text.Chapter;
import com.lowagie.text.Document;
import com.lowagie.text.Font;
import com.lowagie.text.Image;
import com.lowagie.text.List;
import com.lowagie.text.ListItem;
import com.lo ......
import java.util.Scanner;
public class Game{
void welcome(){
println("»¶ÓÀ´µ½¼ôµ¶Ê¯Í·²¼ÓÎÏ·");
}
Choice getUserChoice(){
println("ÇëÑ¡Ôñ\t[1]¼ôµ¶\t[2]ʯͷ\t[3]²¼");
Scanner sc= new Scanner(System.in);
int userCh ......
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