Exception in thread "main" java.util.IllegalFormatConversionException: d != java .lang.String at java.util.Formatter$FormatSpecifier.failConversion(Formatter.java:397 8) at java.util.Formatter$FormatSpecifier.printInteger(Formatter.java:2705) at java.util.Formatter$FormatSpecifier.print(Formatter.java:2658) at java.util.Formatter.format(Formatter.java:2430) at java.io.PrintStream.format(PrintStream.java:899) at java.io.PrintStream.printf(PrintStream.java:800) at HelloWorld.main(HelloWorld.java:9) Press any key to continue... 报这个错误信息 public class HelloWorld { public static void main(String args[]) { String year="2007"; String month="3"; String day="2"; String hour="3"; String minute="32"; String second="33"; System.out.printf("%04d-%02d-%02d %02d:%02d:%02d",year,month,day,hour,minute,second); } }
int year=2007; int month=3; int day=2; int hour=3; int minute=32; int second=33;
String month="3";
String date="2";
System.out.printf("%s-%s-%s",year,month,date);
String month="3";
String date="2";
System.out.printf(year+"-"+month+"-"+date......);
System.out.printf("%04d-%02d-%02d %02d:%02d:%02d",year, month, day, hour, minute, second));
------------------------------------------------------------------------------
不完全认同。
你试试System.out.printf("%.4d-%.2d-%.2d %.2d:%.2d:%.2d",year, month, day, hour, minute, second));
.lang.String
at java.util.Formatter$FormatSpecifier.failConversion(Formatter.java:397
8)
at java.util.Formatter$FormatSpecifier.printInteger(Formatter.java:2705) at java.util.Formatter$FormatSpecifier.print(Formatter.java:2658)
at java.util.Formatter.format(Formatter.java:2430)
at java.io.PrintStream.format(PrintStream.java:899)
at java.io.PrintStream.printf(PrintStream.java:800)
at HelloWorld.main(HelloWorld.java:9)
Press any key to continue...
报这个错误信息
public class HelloWorld {
public static void main(String args[]) {
String year="2007";
String month="3";
String day="2";
String hour="3";
String minute="32";
String second="33";
System.out.printf("%04d-%02d-%02d %02d:%02d:%02d",year,month,day,hour,minute,second);
}
}
int year=2007;
int month=3;
int day=2;
int hour=3;
int minute=32;
int second=33;
try {
System.out.printf("%04d-%02d-%02d %02d:%02d:%02d",year,month,day,hour,minute,second);
}
catch (Exception ex) {
System.out.println(ex);
}
System.out.printf("程序输出完毕");
是int 不是String
public static void main(String args[]) {
String year="2007";
String month="3";
String day="2";
String hour="3";
String minute="32";
String second="33";
System.out.printf(year+"-"+month+"-"+day+" "+hour+":"+minute+":"+second);
}
}
import java.util.Date;
import java.text.SimpleDateFormat;public class HelloWorld {
public static void main(String args[]) {
//把要格式化的时间 写成下面的字符串
Date d = new Date("2007/3/30 3:32:33");
//格式化时间
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
//输出
System.out.println(sdf.format(d));
}
}次方法用于格式化系统时间
输出结果如:2007-03-30 13:51:51
如果Date 不传参数 则打出的是系统时间
你可以查 JDK 的 Date类 SimpleDateFormat类 还有抽象类 Calenar