Converting, Replacing and Splitting Strings

-
The String class provides the methods for converting, replacing and splitting strings as given in table.

java.lang.String
Method syntax Return type Description
+toLowerCase() String Returns a new string with all characters converted to lowercase
+toUpperCase() String Returns a new string with all characters converted to uppercase
+trim() String Returns a new string with blank characters trimmed on both sides
+replace(oldChar:char, newChar:char) String Returns a new string that replaces all matching characters in this string with the new character
+replaceFirst(oldString:String, newString:String) String Returns a new string that replaces the first matching substring in this string with the new substring
+replaceAll(oldString:String, newString:String) String Returns a new string that replaces all matching substrings in this string with the new substring
+split(delimeter:String) String[] Returns an array of strings consisting of the substrings split by the delimiter


Once a string is created, its contents cannot be changed, The methods toLowerCase, toUpperCase, trim, replace, replaceFirst and replaceAll return a new string derived from the original string(without changing the original string!). The toLowerCase and toUpperCase mehtod return a new string by converting all the characters in the string to lowercase or uppercase. The trim method retruns a new string by eliminating blank characters from both ends of the string. Several versions of the replace methods are provided to replace a character or a substring in the string with a new character or a new substring.

Popular posts from this blog

Shutdown Pc

-
Image
#include<iostream> #include<stdlib.h> #include<conio.h> using namespace std; int main() {    int ch;   while(1)   {   cout<<"1. Shutdown\n2. Open TaskManager\n3. Open My Documents.\n4. Exit\nChoice : ";   cin>>ch;     switch (ch)   {   case 1:       system("C:\\WINDOWS\\System32\\shutdown /s");       break; case 2: system("C:\\WINDOWS\\System32\\taskmgr /s"); break; case 3: system("C:\\WINDOWS\\explorer /s"); break; case 4: return 0; } }   getch();     return 0; } Output:
Read more

Ellipse using OpenGl

-
#include<gl/glut.h> #include<gl/glu.h> #include<gl/gl.h> #include<iostream> using namespace std; int xc=0,yc=0,rx=40,ry=60; void display() { float rxsq=rx*rx; float rysq=ry*ry; float x=0,y=ry,p; float px=0,py=2*rxsq*y; glClear(GL_COLOR_BUFFER_BIT); glPointSize(1); glBegin(GL_POINTS); glVertex2i(xc+x,yc+y); glVertex2i(-(xc+x),-(yc+y)); cout<<xc+x<<" "<<yc+y<<endl; p=rysq-(rxsq-ry)+(0.25*rxsq); while(px<py) { x++; px=px+2*rysq; if(p<0) p=p+rysq+px; else { y--; py=py-2*rxsq; p=p+rysq+px-py; } glVertex2i(xc+x,yc+y); glVertex2i(xc+x,-(yc+y)); glVertex2i(-(xc+x),yc+y); glVertex2i(-(xc+x),-(yc+y)); cout<<xc+x<<" "<<yc+y<<endl; } p=rysq*(x+0.5)*(x+0.5) + rxsq*(y-1)*(y-1) -rxsq*rysq; while(y>0) { y--; py=py-2*rxsq; if(p>0) { p=p+rxsq-py; } else { x++; px=px+2*rysq
Read more

String Comparisons

-
The String class provides the methods for comparing strings, as given below:-                       Method                                                            Defination str2.equals(s1: String): boolean                        Returns true if this string is equal to string s1. str2.equalsIgnoreCase(s1: String): boolean      Returns true if this string is equal to string s1 case                                                                                   insensitive. str2.compareTo(s1: String): int                        Returns an integer greater than 0, equal to 0, or less                                                                                 than 0 to indicate whether this string is greater than,                                                                                 equal to, or less than s1. str2.compareToIgnoreCase(s1: String): int      Same as compareTo except that the comparison is case                                                      
Read more