转载自：飞扬青春sina blog

java字符串大小写转换的两种方法

import java.io..*

public class convertToPrintString

 {   

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

       {

            InputStreamReader reader = new InputStreamReader(System.in); 

            BufferedReader input = new BufferedReader(reader); 

            System.out.print("Please enter your word:"); 

            String text =  input.readLine(); 

            String s = convertString(text); 

            System.out.println(s);

        }

        //第一种方法

       public static String convertString(String src)

       {

            char[] array = src.toCharArray();

             int temp = 0;

             for (int i = 0; i < array.length; i++)

             {

                 temp = (int) array[i];

                 if (temp <= 90 && temp >= 65)

                 { // array[i]为大写字母

                     array[i] = (char) (temp + 32);

                 } else if (temp <= 122 && temp >= 97)

                           { // array[i]为小写字母

                                array[i] = (char) (temp - 32);

                 }

              }

              return String.valueOf(array);

          }

          //第二种方法

           public static String convertString(String str)

           {

               String upStr = str.toUpperCase(); 

               String lowStr = str.toLowerCase(); 

               StringBuffer buf = new StringBuffer(str.length()); 

               for(int i=0;i

               { 

                  if(str.charAt(i)==upStr.charAt(i))

                  { 

                      buf.append(lowStr.charAt(i)); 

                  }

                 else

                 {

                     buf.append(upStr.charAt(i)); 

                  } 

                } 

                return   buf.toString(); 

             }

 ｝