//包裝類 8種基本數(shù)據(jù)類型對(duì)應(yīng)著一個(gè)類，此類即為包裝類
public class TestWrapper {
 
  //基本數(shù)據(jù)類型、包裝類與String類之間的轉(zhuǎn)換
  @Test
  public void test2() {
    //基本數(shù)據(jù)類型、包裝類 -----> String類:調(diào)用String類的靜態(tài)的重載的valueOf（Xxx x）方法
 
    int i1 = 10;
    String str1 = i1 + ""; //"10"
 
    String str2 = String.valueOf(i1);
    String str3 = String.valueOf(true);
    System.out.println(str3);
    //String類 ----> 基本數(shù)據(jù)類型、包裝類:調(diào)用包裝類的parseXxx（String str）方法
    int i3 = Integer.parseInt(str2);
    System.out.println(i3);
    boolean b1 = Boolean.parseBoolean(str3);
    System.out.println(b1);
 
    //int i4 = (int)str2;
  }
 
  @Test
  public void test1() {
    int i = 10;
    System.out.println(i);
    boolean b = false;
 
    //基本數(shù)據(jù)類型 ----> 對(duì)應(yīng)的包裝類：調(diào)用包裝類的構(gòu)造器
    Integer i1 = new Integer(i);
    System.out.println(i1.toString());
 
    Float f = new Float("12.3F");
    System.out.println(f);
 
    //java.lang.NumberFormatException
//    i1 = new Integer("12abc");
//    System.out.println(i1);
 
    //對(duì)于Boolean來講，當(dāng)形參是“true”返回true，除此之外返回false。
    Boolean b1 = new Boolean("false");
    System.out.println(b1);
 
    b1 = new Boolean("true1abc");
    System.out.println(b1);
 
    BBB bbb = new BBB();
    System.out.println(bbb.b);
 
    //包裝類 -----> 基本數(shù)據(jù)類型:調(diào)用包裝類xx的xxValue（）方法
    int i2 = i1.intValue();
    System.out.println(i2);
    float f1 = f.floatValue();
    System.out.println(f1);
    boolean b2 = b1.booleanValue();
    System.out.println(b2);
 
    //JDK5.0以后，自動(dòng)裝箱和拆箱
    int i4 = 12;
    Integer i3 = i4; //自動(dòng)裝箱
    Boolean bb = false;
 
    int i5 = i3; //自動(dòng)拆箱
  }
}
 
class BBB {
  Boolean b;
}