扫描仪类findInLine()方法 (Scanner Class findInLine() method)

Syntax:

句法：

    public String findInLine(Pattern patt);
    public String findInLine(String patt);

• findInLine() method is available in java.util package.

  findInLine()方法在java.util包中可用。

• findInLine(Pattern patt) method is used to get the string that meets the given pattern (Pattern).

  findInLine(Pattern patt)方法用于获取符合给定模式(Pattern)的字符串。

• findInLine(String patt) method is used to get the string that meets the given String (patt).

  findInLine(String patt)方法用于获取符合给定String(patt)的字符串。

• These methods may throw an exception at the time of returning pattern.

  这些方法在返回模式时可能会引发异常。

  IllegalStateException: This exception may throw when this Scanner is not opened.

  IllegalStateException ：如果未打开此扫描器，则可能引发此异常。

• These are non-static methods, it is accessible with class object & if we try to access these methods with the class name then we will get an error.

  这些是非静态方法，可通过类对象访问；如果尝试使用类名称访问这些方法，则会收到错误消息。

Parameter(s):

参数：

• In the first case, findInLine(Pattern patt),

  在第一种情况下， findInLine(Pattern patt) ，

  • Pattern patt – represents the pattern to find for.
  • 模式patt –表示要查找的模式。

• In the second case, findInLine(String patt),

  在第二种情况下， findInLine(String patt) ，

  • String patt – represents the string denotes the pattern to find for.
  • 字符串patt –表示字符串，表示要查找的模式。

Return value:

返回值：

In both the cases, the return type of the method is String, it returns the message that meets the given pattern.

在这两种情况下，方法的返回类型均为String ，它返回符合给定模式的消息。

Example:

例：

// Java program is to demonstrate the
// example of findInLine

import java.util.*;
import java.util.*;
import java.util.regex.*;

public class FindInLine {
 public static void main(String[] args) {
  String str = "Java Programming! 3 * 8= 24";

  // Instantiates Scanner
  Scanner sc = new Scanner(str);

  // By using findInLine(Pattern) method
  // is to find the next pattern from the given
  // parameter ".Program"
  String pattern = sc.findInLine(Pattern.compile(".Program"));
  System.out.println("sc.findInLine(Pattern.compile(.Program)): " + pattern);

  // By using findInLine(string) method
  // is to find the next pattern from the given
  // parameter of string "Java"

  pattern = sc.findInLine("ava");
  System.out.println("sc.findInLine(ava): " + pattern);

  // Scanner closed
  sc.close();
 }
}

Output

输出量

sc.findInLine(Pattern.compile(.Program)):  Program
sc.findInLine(ava): null

翻译自: https://www.includehelp.com/java/scanner-findinline-method-with-example.aspx