Javaの部分文字列

Java 部分文字列とは何ですか?

Javaで部分文字列を使用する方法

String s = "CodeGym";
System.out.println(s.substring(4));
//returns Gym

String s = "CodeGym"; 
System.out.println(s.substring(2,5));
//returns deG

• Javaで部分文字列を取得する方法
• 指定された文字列のすべての部分文字列を検索する方法
• 最長の共通部分文字列を見つける方法

Java で部分文字列を取得する方法 (特に)

import java.io.IOException;

public class Main {

   public static void main(String[] args) throws IOException {

       String s1 = "the best Java Core course is CourseCodeGym.  End of story";
       String myTarget = "CodeGym";
       int index1 = s1.indexOf(myTarget);
      
       int index2 = index1 + myTarget.length();
       System.out.println(s1.substring(index1, index2));

   }
}

import java.io.IOException;
public class Main {
   public static void main(String[] args) throws IOException {
       String myTarget = "CodeGym";
       for (int i = 0; i < myTarget.length(); i++) {
           for (int j = i + 1; j <= myTarget.length(); j++) {
               System.out.println(myTarget.substring(i, j));
           }
       }    
   }
}

String first = "CodeGym" 
String second = "SomeGym"

public class SubStringTest {

   //  in this method we are looking for the Longest common substring of
   // first String with length = m  and the second String with length = n
   public static String longestCS(String first, String second, int m, int n) {
       // the maximal length
       int maxLength = 0;
       // the last index of the longest common substring
       int endIndex = m;

       // array stores the length of substring
       int[][] keeper = new int[m + 1][n + 1];

       for (int i = 1; i <= m; i++) {
           for (int j = 1; j <= n; j++) {
               // check if current characters of first and second strings match
               if (first.charAt(i - 1) == second.charAt(j - 1)) {
                   keeper[i][j] = keeper[i - 1][j - 1] + 1;
                  
                   if (keeper[i][j] > maxLength) {
                       maxLength = keeper[i][j];
                       endIndex = i;
                   }
               }
           }
       }
       return first.substring(endIndex - maxLength, endIndex);
   }


   public static void main(String[] args) {
       String first = "CodeGym";
       String second = "SomeGym";
       int m = first.length(), n = second.length();
       System.out.println("The longest common substring = " + longestCS(first, second, m, n));
   }
}

Java で部分文字列はどのように機能しますか

String x = "CodeGymIsTheBest";
String y = x.substring (2,6);
String z = x.substring (0,3);

JDK 6 バージョンの部分文字列

String x = "CodeGymIsTheBest";
String y = x.substring (2,6);
String z = x.substring (0,3);