Java の例 - 接続文字列

//StringConcatenate.java 文件
public class StringConcatenate{
   public static void main(String[] args){
      long startTime = System.currentTimeMillis();
      for(int i=0;i<5000;i++){
         String result = "This is"
         + "testing the"
         + "difference"+ "between"
         + "String"+ "and"+ "StringBuffer";
      }
      long endTime = System.currentTimeMillis();
      System.out.println("字符串连接" 
      + " - 使用 + 操作符 : " 
      + (endTime - startTime)+ " ms");
      long startTime1 = System.currentTimeMillis();
      for(int i=0;i<5000;i++){
         StringBuffer result = new StringBuffer();
         result.append("This is");
         result.append("testing the");
         result.append("difference");
         result.append("between");
         result.append("String");
         result.append("and");
         result.append("StringBuffer");
      }
      long endTime1 = System.currentTimeMillis();
      System.out.println("字符串连接" 
      + " - 使用 StringBuffer : "
      + (endTime1 - startTime1)+ " ms");
   }}

字符串连接 - 使用 + 操作符 : 0 ms 
字符串连接 - 使用 StringBuffer : 42 ms