blocks|key|85084|text|在标准Java中没有纯粹的scanf替代，但是您可以使用java.util.Scanner来解决使用scanf解决的相同问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|85085|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/1.7/docs/api/java/util/Scanner.html^0|S|H|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

There is not a pure scanf replacement in standard Java, but you could use a <a href="http://docs.oracle.com/javase/1.7/docs/api/java/util/Scanner.html" rel="noreferrer">java.util.Scanner</a> for the same problems you would use scanf to solve.

blocks|key|302533|text|看看this+site，它解释了两种从java控制台读取数据的方法，分别是使用Scanner或System.in中的经典InputStreamReader。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|302534|以下代码取自引用的网站：|302535|import+java.io.BufferedReader;
import+java.io.IOException;
import+java.io.InputStreamReader;

public+class+ReadConsoleSystem+{
++public+static+void+main(String[]+args)+{

++++System.out.println("Enter+something+here+:+");

++++try{
++++++++BufferedReader+bufferRead+=+new+BufferedReader(new+InputStreamReader(System.in));
++++++++String+s+=+bufferRead.readLine();

++++++++System.out.println(s);
++++}
++++catch(IOException+e)
++++{
++++++++e.printStackTrace();
++++}

++}
}|code-block|syntax|javascript|302536|--|302537|import+java.util.Scanner;

public+class+ReadConsoleScanner+{
++public+static+void+main(String[]+args)+{

++++++System.out.println("Enter+something+here+:+");

+++++++String+sWhatever;

+++++++Scanner+scanIn+=+new+Scanner(System.in);
+++++++sWhatever+=+scanIn.nextLine();

+++++++scanIn.close();++++++++++++
+++++++System.out.println(sWhatever);
++}
}|302538|致以问候。|302539|entityMap|0|LINK|mutability|MUTABLE|url|http://www.mkyong.com/java/how-to-read-input-from-console-java^0|13|7|1O|H|2|9|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@$9|11|A|12|B|C]|$9|13|A|14|B|C]]|D|@$9|15|A|16|1|17]]|E|$]]|$1|F|3|G|5|6|7|18|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|19|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|1A|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|1B|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|1C|8|@]|D|@]|E|$]]|$1|S|3|-4|5|6|7|1D|8|@]|D|@]|E|$]]]|T|$U|$5|V|W|X|E|$Y|Z]]]]

Take a look at <a href="http://www.mkyong.com/java/how-to-read-input-from-console-java">this site</a>, it explains two methods for reading from console in java, using <code>Scanner</code> or the classical <code>InputStreamReader</code> from System.in.

Following code is taken from cited website:

<pre><code>import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class ReadConsoleSystem {
 public static void main(String[] args) {

 System.out.println("Enter something here : ");

 try{
 BufferedReader bufferRead = new BufferedReader(new InputStreamReader(System.in));
 String s = bufferRead.readLine();

 System.out.println(s);
 }
 catch(IOException e)
 {
 e.printStackTrace();
 }

 }
}
</code></pre>

--

<pre><code>import java.util.Scanner;

public class ReadConsoleScanner {
 public static void main(String[] args) {

 System.out.println("Enter something here : ");

 String sWhatever;

 Scanner scanIn = new Scanner(System.in);
 sWhatever = scanIn.nextLine();

 scanIn.close(); 
 System.out.println(sWhatever);
 }
}
</code></pre>

Regards.

blocks|key|302592|text|您可以将输出格式化为Java，如下面的代码片段所述。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|302593|public+class+TestFormat+{

++++public+static+void+main(String[]+args)+{
++++++long+n+=+461012;
++++++System.out.format("%25d%25n",+n);++++++//++-->++"461012"
++++++System.out.format("%2508d%25n",+n);++++//++-->++"00461012"
++++++System.out.format("%25%2B8d%25n",+n);++++//++-->++"+%2B461012"
++++++System.out.format("%25,8d%25n",+n);++++//+-->++"+461,012"
++++++System.out.format("%25%2B,8d%25n%25n",+n);+//++-->++"%2B461,012"
+++}
}|code-block|syntax|javascript|302594|你可以阅读更多here.|offset|length|302595|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.oracle.com/javase/tutorial/java/data/numberformat.html^0|0|0|7|5|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

You can format your output in Java as described in below code snippet.

<pre><code>public class TestFormat {

 public static void main(String[] args) {
 long n = 461012;
 System.out.format("%d%n", n); // --&gt; "461012"
 System.out.format("%08d%n", n); // --&gt; "00461012"
 System.out.format("%+8d%n", n); // --&gt; " +461012"
 System.out.format("%,8d%n", n); // --&gt; " 461,012"
 System.out.format("%+,8d%n%n", n); // --&gt; "+461,012"
 }
}
</code></pre>

You can read more <a href="https://docs.oracle.com/javase/tutorial/java/data/numberformat.html" rel="nofollow">here.</a>

blocks|key|302640|text|如果人们真的想这样做，他们可以制作自己的scanf()版本，比如：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|302641|++++import+java.util.ArrayList;
++++import+java.util.Scanner;

public+class+Testies+{

public+static+void+main(String[]+args)+{
++++ArrayList<Integer>+nums+=+new+ArrayList<Integer>();
++++ArrayList<String>+strings+=+new+ArrayList<String>();

++++//+get+input
++++System.out.println("Give+me+input:");
++++scanf(strings,+nums);

++++System.out.println("Ints+gathered:");
++++//+print+numbers+scanned+in
++++for(Integer+num+:+nums){
++++++++System.out.print(num+%2B+"+");
++++}
++++System.out.println("\nStrings+gathered:");
++++//+print+strings+scanned+in
++++for(String+str+:+strings){
++++++++System.out.print(str+%2B+"+");
++++}

++++System.out.println("\nData:");
++++for(int+i=0;+i<strings.size();+i%2B%2B){
++++++++System.out.println(nums.get(i)+%2B+"+"+%2B+strings.get(i));
++++}
}

//+get+line+from+system
public+static+void+scanf(ArrayList<String>+strings,+ArrayList<Integer>+nums){
++++Scanner+getLine+=+new+Scanner(System.in);
++++Scanner+input+=+new+Scanner(getLine.nextLine());

++++while(input.hasNext()){
++++++++//+get+integers
++++++++if(input.hasNextInt()){
++++++++++++nums.add(input.nextInt());
++++++++}
++++++++//+get+strings
++++++++else+if(input.hasNext()){
++++++++++++strings.add(input.next());
++++++++}
++++}
}

//+pass+it+a+string+for+input
public+static+void+scanf(String+in,+ArrayList<String>+strings,+ArrayList<Integer>+nums){
++++Scanner+input+=+(new+Scanner(in));

++++while(input.hasNext()){
++++++++//+get+integers
++++++++if(input.hasNextInt()){
++++++++++++nums.add(input.nextInt());
++++++++}
++++++++//+get+strings
++++++++else+if(input.hasNext()){
++++++++++++strings.add(input.next());
++++++++}
++++}
}


}|code-block|syntax|javascript|302642|显然，我的方法只检查字符串和整数，如果您希望处理不同的数据类型，请添加适当的arraylist并检查它们。此外，hasNext()可能应该在if-else+if序列的底部，因为hasNext()将为字符串中的所有数据返回true。|302643|输出：|302644|Give+me+input:+++++++++apples+8+9+pears+oranges+5+++++++++Ints+gathered:+++++++++8+9+5++++++++++Strings+gathered:+++++++++apples+pears+oranges++++++++++Data:+++++++++8+apples+++++++++9+pears+++++++++5+oranges|302645|可能不是最好的例子；但是，重点是Scanner实现了Iterator类。这使得使用hasNext<datatypehere>()方法迭代扫描仪输入变得很容易；然后存储输入。|302646|entityMap^0|K|7|0|0|1K|9|1Y|A|2G|9|0|0|0|5S|0|G|7|Q|8|15|N|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|Y|8|@$9|Z|A|10|B|C]|$9|11|A|12|B|C]|$9|13|A|14|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|15|8|@]|D|@]|E|$]]|$1|O|3|P|5|6|7|16|8|@$9|17|A|18|B|C]]|D|@]|E|$]]|$1|Q|3|R|5|6|7|19|8|@$9|1A|A|1B|B|C]|$9|1C|A|1D|B|C]|$9|1E|A|1F|B|C]]|D|@]|E|$]]|$1|S|3|-4|5|6|7|1G|8|@]|D|@]|E|$]]]|T|$]]

If one really wanted to they could make there own version of <code>scanf()</code> like so:

<pre><code> import java.util.ArrayList;
 import java.util.Scanner;

public class Testies {

public static void main(String[] args) {
 ArrayList&lt;Integer&gt; nums = new ArrayList&lt;Integer&gt;();
 ArrayList&lt;String&gt; strings = new ArrayList&lt;String&gt;();

 // get input
 System.out.println("Give me input:");
 scanf(strings, nums);

 System.out.println("Ints gathered:");
 // print numbers scanned in
 for(Integer num : nums){
 System.out.print(num + " ");
 }
 System.out.println("\nStrings gathered:");
 // print strings scanned in
 for(String str : strings){
 System.out.print(str + " ");
 }

 System.out.println("\nData:");
 for(int i=0; i&lt;strings.size(); i++){
 System.out.println(nums.get(i) + " " + strings.get(i));
 }
}

// get line from system
public static void scanf(ArrayList&lt;String&gt; strings, ArrayList&lt;Integer&gt; nums){
 Scanner getLine = new Scanner(System.in);
 Scanner input = new Scanner(getLine.nextLine());

 while(input.hasNext()){
 // get integers
 if(input.hasNextInt()){
 nums.add(input.nextInt());
 }
 // get strings
 else if(input.hasNext()){
 strings.add(input.next());
 }
 }
}

// pass it a string for input
public static void scanf(String in, ArrayList&lt;String&gt; strings, ArrayList&lt;Integer&gt; nums){
 Scanner input = (new Scanner(in));

 while(input.hasNext()){
 // get integers
 if(input.hasNextInt()){
 nums.add(input.nextInt());
 }
 // get strings
 else if(input.hasNext()){
 strings.add(input.next());
 }
 }
}


}
</code></pre>

Obviously my methods only check for Strings and Integers, if you want different data types to be processed add the appropriate arraylists and checks for them. Also, <code>hasNext()</code> should probably be at the bottom of the <code>if-else if</code> sequence since <code>hasNext()</code> will return true for all of the data in the string.

Output:

<code>Give me input:
 apples 8 9 pears oranges 5
 Ints gathered:
 8 9 5 
 Strings gathered:
 apples pears oranges 
 Data:
 8 apples
 9 pears
 5 oranges</code>

Probably not the best example; but, the point is that <code>Scanner</code> implements the <code>Iterator</code> class. Making it easy to iterate through the scanners input using the <code>hasNext&lt;datatypehere&gt;()</code> methods; and then storing the input.

blocks|key|302652|text|还有一个更简单的答案|type|unstyled|depth|inlineStyleRanges|entityRanges|data|302653|import+java.io.BufferedReader;
import+java.util.Scanner;

public+class+Main+{

++++public+static+void+main(String[]+args)
++++{
++++++++String+myBeautifulScanf+=+new+Scanner(System.in).nextLine();
++++++++System.out.println(+myBeautifulScanf+);

++++}
}|code-block|syntax|javascript|302654|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

THERE'S an even simpler answer

<pre><code>import java.io.BufferedReader;
import java.util.Scanner;

public class Main {

 public static void main(String[] args)
 {
 String myBeautifulScanf = new Scanner(System.in).nextLine();
 System.out.println( myBeautifulScanf );

 }
}
</code></pre>

blocks|key|85283|text|不是等效项，但您可以使用Scanner和模式来解析由空格分隔的三个非负数的行，例如：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|85284|71+5796+2489
88+1136+5298
42+420+842|code-block|syntax|javascript|85285|下面是使用findAll的代码|offset|length|style|CODE|85286|new+Scanner(System.in).findAll("(\\d%2B)+(\\d%2B)+(\\d%2B)")
++++++++.forEach(result+->+{
++++++++++++int+fst+=+Integer.parseInt(result.group(1));
++++++++++++int+snd+=+Integer.parseInt(result.group(2));
++++++++++++int+third+=+Integer.parseInt(result.group(3));
++++++++++++int+sum+=+fst+%2B+snd+%2B+third;
++++++++++++System.out.printf("%25d+%2B+%25d+%2B+%25d+=+%25d",+fst,+snd,+third,+sum);
++++++++});|85287|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/Scanner.html#findAll(java.lang.String))^0|0|0|5|7|5|7|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Y|8|@$I|Z|J|10|K|L]]|9|@$I|11|J|12|1|13]]|A|$]]|$1|M|3|N|5|D|7|14|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]]]

Not an equivalent, but you can use a Scanner and a pattern to parse lines with three non-negative numbers separated by spaces, for example:

<pre><code>71 5796 2489
88 1136 5298
42 420 842
</code></pre>

Here's the code using <a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/Scanner.html#findAll(java.lang.String)" rel="nofollow noreferrer"><code>findAll</code></a>:

<pre><code>new Scanner(System.in).findAll("(\\d+) (\\d+) (\\d+)")
 .forEach(result -&gt; {
 int fst = Integer.parseInt(result.group(1));
 int snd = Integer.parseInt(result.group(2));
 int third = Integer.parseInt(result.group(3));
 int sum = fst + snd + third;
 System.out.printf("%d + %d + %d = %d", fst, snd, third, sum);
 });
</code></pre>

Java has the notion of <a href="https://docs.oracle.com/javase/7/docs/api/java/util/Formatter.html#syntax" rel="nofollow noreferrer">format strings</a>, bearing a strong resemblance to <a href="https://en.wikipedia.org/wiki/Printf_format_string" rel="nofollow noreferrer">format strings in other languages</a>. It is used in JDK methods like <a href="https://docs.oracle.com/javase/7/docs/api/java/lang/String.html#format(java.lang.String,%20java.lang.Object...)" rel="nofollow noreferrer"><code>String#format()</code></a> for output conversion.
I was wondering if there's an input conversion method akin to <a href="https://linux.die.net/man/3/scanf" rel="nofollow noreferrer">C's <code>scanf</code></a> in Java?

Is there an equivalent method to C's scanf in Java?

Java

Java具有与非常相似的概念。它在等JDK方法中用于输出转换。我想知道在Java中是否有类似于的输入转换方法？

问在Java中有没有与C的scanf等价的方法？
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