?import?java.util.Arrays;import?java.util.Calendar;import?java.util.Date;public?interface?Iqianqian?{ public?static?void?main?(String[]?args){?Calendar?Q=Calendar.getInstance(); Date?date=Q.getTime(); Long?time=Q.getTimeInMillis();?int?year=Q.get(Calendar.YEAR);?int?month=Q.get(Calendar.MONTH)+1; int?day=Q.get(Calendar.DAY_OF_MONTH); int?hour=Q.get(Calendar.HOUR_OF_DAY); int?minute=Q.get(Calendar.MINUTE);?int?second=Q.get(Calendar.SECOND); System.out.println("您好北京時間；"?+date); System.out.println("小Q報時；"+year+"年"+month+"月"+day+"??"+hour+"；"+minute+"；"+second);????System.out.println("毫秒數；?"+time);}?public?static?void?methodtwo(){ String?Q="?Hello?lan?qian?is?a?good?girl??"; System.out.println("字符串長度："?+Q.length()); System.out.println("轉換為大寫："?+Q.toUpperCase());?System.out.println("子串為："?+Q.substring(6,30)); String?q1=Q.replace("good","beatuiful"); System.out.println("替換為："?+Q.replace("good","beatuiful")); System.out.println("刪除字符串兩邊多余的空格："?+Q.trim()); System.out.println("qian的位置:?"?+Q.indexOf("qian"));????String[]?arr=Q.split("?");????System.out.println("把空格拆成數組?；?"?+Arrays.toString(arr));????byte[]?q2=Q.getBytes();????System.out.print("轉換為字節數數組：?");????for(int?i=0;i<q2.length;i++){????System.out.print(q2[i]+?"?");????} } public?static?void?methodthree(){????int[]?Q=new?int?[20]; ?for(int?i=1;i<20;i++)?????{??? ??Q[i]=(int)(Math.random()*100); ?Arrays.sort(Q);?System.out.print(Q[i]+"?");} }????????public??static?void?methodfour(){ ????int?score=110; Integer?englishscore=new?Integer(score); ???String?str="108"; ???int?mathscore=Integer.valueOf(str); ??double?chinesescore=englishscore.doubleValue(); ???int?sum=(int)?(mathscore+score+chinesescore); ???int?averge=(sum/3);????System.out.println("三門課總成績；"+sum);????System.out.println("三門課平均成績；"+averge); }?static?double?doubleValue()?{ //?TODO?Auto-generated?method?stub return?110; }?static?int?valueOf(String?str)?{ //?TODO?Auto-generated?method?stub return?108; } } ? ? ??