APCS/01 Strings/02a StringMethods/StringMethods.java

//Name: 
//Date: 
public class StringMethods
{
   public static void main(String[] args)
   {
      String s = "Internet",  s2 = "net", s3 = "   Internet ";
      
      String s7 = s.substring(5);   			//  
      String s8 = s.substring(0, 5);			// 
      String s9 = s.substring(2, 6);			//
      
      int pos11 = s.indexOf('e');				// 
      int pos12 = s.indexOf('x');				// 
      int pos13 = s.indexOf('e', 4);			// 
      int pos14 = s.lastIndexOf('e');			// 
      int pos15 = s.lastIndexOf('e', 4);		// 	
      int pos16 = s.lastIndexOf('e', 2);		// 
      int pos17 = s.indexOf(s2);					// 
      int pos18 = s.indexOf(s2, 6);		   	// 
      int pos19 = s.lastIndexOf(s2);	 		// 
      int pos20 = s.lastIndexOf(s2, 6);		// 
      
      boolean isSame22 = s.equals(s2);			//
      boolean isSame23 = s.equalsIgnoreCase("internet");// 
      int result24 = s.compareTo("internet");// 
      int result25 = s2.compareTo(s);			// 
      int result26 = s.compareToIgnoreCase("internet");// 
   	
      String s28 = s.toUpperCase();				//
      String s29 = s.replace('n', 'N');		//
      String s30 = s3.trim();						//
   	// no String method changes the String object for which they are
   	// called.  They build and return a new string instead. For example,
   	// s3.replace('a','A') by itself is useless, because s3 remains unchanged.
   	// The technical term is "immutable," as in "Strings are immutable."
   	
      char ch = s.charAt(0);								// 
      boolean isSame36 = (ch == 'I');					// 
      boolean isLetter37 = Character.isLetter(ch);	// 
      boolean isCap38 = Character.isUpperCase(ch); // 
      char ch39 = Character.toLowerCase(ch);			// 
      String s40 = ch39 + s.substring(1);				// 
   	// three ways to visit each character of a string
      for(int i = 0; i < s.length(); i++)
         System.out.print(s.substring(i, i+1)+" ");//  
      for(int i = 0; i < s.length(); i++)
         System.out.print(s.charAt(i)+" ");			//  
      char[] chArray = s.toCharArray();
      for(int i = 0; i < chArray.length; i++)		
         System.out.print(chArray[i]+" ");			//  
      System.out.println();
      
      // Strings can be split:   String[] split(String separator)
      // The method split() returns an array of substrings split around 
      // the specified separator, which is then removed
      String[] abra = "ABRACADABRA".split("A");
      for(String str : abra)
         System.out.print(str+" ");                   //
      System.out.println();
      String[] abra2 = "ABRACADABRA".split("BR");
      for(String str : abra2)
         System.out.print(str+" ");                   //
      System.out.println();
      String[] abra3 = "A B R A C A D A B R A".split(" ");
      for(String str : abra3)
         System.out.println(str+" ");                 //
                                                      //
                                                         
      /*   String Methods #1 
      1. The string dateStr represents a date in the format "mm/dd/yyyy".   
      Write a code fragment that changes dateStr to the format "dd-mm-yy".  
      For example, "09/16/2008" becomes "16-09-08".  
      */     
      String dateStr = "10/11/2005";
      String[] times = dateStr.split("/");
      dateStr = times[1] + "-" + times[0] + "-" + times[2].substring(2); 
      System.out.println(dateStr);
      
      /*  String Methods #2  
      2.	Given a line of text, print each word on its own line, but don't 
      print the blank lines.  
      */
      System.out.println();
      String text = "How  are you doing?";
      String[] words = text.split(" ");
      for (int i = 0; i < words.length; i++)
        if (words[i].equals(" "))
            System.out.println(words[i]);
            
      /*   String Methods #3 
      3. Given a line of text, remove all punctuation from that line.
      One way is to replace each punctuation mark with "".
      */      
      String str = "RT @TJCheer2015: Freshman & Sophomores: Interested in cheer at TJ? Email: thomasjeffersoncheer@gmail.com";
      String punct = ",./;:'\"?<>[]{}|`~!@#$%^&*()";
      for (int i = 0; i < punct.length(); i++) {
         str = str.replace(""+punct.charAt(i), "");
      }
      
      System.out.println(str);
      /*   String Methods #4 
      4. Given a line of text, remove all punctuation from that line.
      One way is to keep all characters that are letters or a space.
      */      
      String str2 = "a @galaxy far, far away --right there! on the (TJ planetarium} ceiling. https://t.co/XfoqbyA9JY";
      String letters = " ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
      String cleaned = "";
      for (int i = 0; i < str2.length(); i++)
         for (int j = 0; j < letters.length(); j++)
            if (str2.charAt(i) == letters.charAt(j))
               cleaned += Character.toString(str2.charAt(i));
               
      System.out.println(cleaned);
       
   }
}

   /******************************
I n t e r n e t I n t e r n e t I n t e r n e t 
  BR C D BR 
 A ACADA A 
 A 
 B 
 R 
 A 
 C 
 A 
 D 
 A 
 B 
 R 
 A 
 16-09-08
 Fall
 Sports
 (football,
 golf,
 cheerleading,
 volleyball,
 field
 hockey,
 cross
 country)
 start
 in
 1
 week.
 RT TJCheer2015 Freshman  Sophomores Interested in cheer at TJ Email thomasjeffersoncheergmailcom
 a galaxy far far away right there on the TJ planetarium ceiling httpstcoXfoqbyAJY
 
 ********************************/