immutablestrings.java

来自「java的类库」· Java 代码 · 共 20 行

//: appendixa:ImmutableStrings.java
// From 'Thinking in Java, 2nd ed.' by Bruce Eckel
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
// Demonstrating StringBuffer.

public class ImmutableStrings {
  public static void main(String[] args) {
    String foo = "foo";
    String s = "abc" + foo +
      "def" + Integer.toString(47);
    System.out.println(s);
    // The "equivalent" using StringBuffer:
    StringBuffer sb = 
      new StringBuffer("abc"); // Creates String!
    sb.append(foo);
    sb.append("def"); // Creates String!
    sb.append(Integer.toString(47));
    System.out.println(sb);
  }
} ///:~