我编写了一程序
如下:
public class M
{
public static void main(String[] args)
{
int k = 10; switch (10)
{
case 1:
System.out.println(1);
case 2:
System.out.println(2);
default:
//System.out.println("你好");
assert true: "出现了非预期错误!";
}
System.out.println("啦啦啦啦啦!");
}
}请问我在dos下输入什么命令可以编译M.java 启动断言 并运行本程序呢,
为什么我老启动不起来断言,我运行如下:
----------------------------------------------------------------------
C:\Documents and Settings\hb\桌面\java>java M
啦啦啦啦啦!C:\Documents and Settings\hb\桌面\java>java -ea M
啦啦啦啦啦!C:\Documents and Settings\hb\桌面\java>java M -ea
啦啦啦啦啦!
-----------------------------------------------------------------------
但是运行时还不对
不对!
我运行如下:
C:\Documents and Settings\hb\桌面\java>java -ea
Usage: java [-options] class [args...]
(to execute a class)
or java [-options] -jar jarfile [args...]
(to execute a jar file)where options include:
-client to select the "client" VM
-server to select the "server" VM
-hotspot is a synonym for the "client" VM [deprecated]
The default VM is client. -cp <class search path of directories and zip/jar files>
-classpath <class search path of directories and zip/jar files>
A ; separated list of directories, JAR archives,
and ZIP archives to search for class files.
-D<name>=<value>
set a system property
-verbose[:class|gc|jni]
enable verbose output
-version print product version and exit
-version:<value>
require the specified version to run
-showversion print product version and continue
-jre-restrict-search | -jre-no-restrict-search
include/exclude user private JREs in the version search
-? -help print this help message
-X print help on non-standard options
-ea[:<packagename>...|:<classname>]
-enableassertions[:<packagename>...|:<classname>]
enable assertions
-da[:<packagename>...|:<classname>]
-disableassertions[:<packagename>...|:<classname>]
disable assertions
-esa | -enablesystemassertions
enable system assertions
-dsa | -disablesystemassertions
disable system assertions
-agentlib:<libname>[=<options>]
load native agent library <libname>, e.g. -agentlib:hprof
see also, -agentlib:jdwp=help and -agentlib:hprof=help
-agentpath:<pathname>[=<options>]
load native agent library by full pathname
-javaagent:<jarpath>[=<options>]
load Java programming language agent, see java.lang.instrument -splash:<imagepath>
show splash screen with specified imageC:\Documents and Settings\hb\桌面\java>java M
啦啦啦啦啦!
java -ea M
你自己的类名总要写上吧
我把 assert false: "出现了非预期错误!" ;
这行代码理解错啦!