开始 java _version
显示:java version "1.4.2_10"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_
Java HotSpot(TM) Client VM (build 1.4.2_10-b03, mixed mode)
点击::javac Hello.java
显示:Exception in thread "main" java.lang.NoClassDefFoundError: hello/java
绝对路径也不对?
环境配错了??
C:\Program Files\Java目录下按了:j2sdk1.4.2_10和 j2re1.4.2_10
环境配置:
JAVA_HOME C:\Program Files\Java\j2sdk1.4.2_10
PATH C:\Program Files\Microsoft Visual Studio\Common\Tools\WinNT;C:\Program Files\Microsoft Visual Studio\Common\MSDev98\Bin;C:\Program Files\Microsoft Visual Studio\Common\Tools;%JAVA_HOME%\bin;%JAVA_HOME%\jre\bin CLS
CLASS %JAVA_HOME%\lib;%JAVA_HOME%\lib\tools.jar
显示:java version "1.4.2_10"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_
Java HotSpot(TM) Client VM (build 1.4.2_10-b03, mixed mode)
点击::javac Hello.java
显示:Exception in thread "main" java.lang.NoClassDefFoundError: hello/java
绝对路径也不对?
环境配错了??
C:\Program Files\Java目录下按了:j2sdk1.4.2_10和 j2re1.4.2_10
环境配置:
JAVA_HOME C:\Program Files\Java\j2sdk1.4.2_10
PATH C:\Program Files\Microsoft Visual Studio\Common\Tools\WinNT;C:\Program Files\Microsoft Visual Studio\Common\MSDev98\Bin;C:\Program Files\Microsoft Visual Studio\Common\Tools;%JAVA_HOME%\bin;%JAVA_HOME%\jre\bin CLS
CLASS %JAVA_HOME%\lib;%JAVA_HOME%\lib\tools.jar
这是个异常是说明你的main有错误或者你根本就没有main,java是严格区分大小写的是不是你的javac Hello.java与你文件名字不一样,出你的文件是hello.java吗?
我安装的是JDK1.6我的bin目录是C:\Program Files\Java\jdk1.6.0\bin 在path路径里设,初学你只要指定bin目录就行了,
你的这个Hello.java在哪个文件夹里,你要指出它的文件路径。
你明和CMD编译的吗?你以后可以用JCreator 编译,就不用关心路径问题,但初学建议还是CMD DOS环境中练习.
{
public static void main(String args[])
{
System.out.println("Hello World");
}
}
存在C:\Program Files\Java\HelloWorld.java
我进入DOS打: javac C:\Program Files\Java\HelloWorld.java
还是有错 显示:Exception in thread "main" java.lang.NoClassDefFoundError: C:\Program
{
public static void main(String args[])
{
System.out.println("Hello World");
}
}
存在C:\Program Files\Java\HelloWorld.java(此图标:不是JAVA 标志)
我进入DOS打:C:\Documents and Settings\-1>javac C:\Program Files\Java\HelloWorld.java
显示:
javac: invalid flag: C:\Program
Usage: javac <options> <source files>
where possible options include:
-g Generate all debugging info
-g:none Generate no debugging info
-g:{lines,vars,source} Generate only some debugging info
-nowarn Generate no warnings
-verbose Output messages about what the compiler is doing
-deprecation Output source locations where deprecated APIs are us
ed
-classpath <path> Specify where to find user class files
-sourcepath <path> Specify where to find input source files
-bootclasspath <path> Override location of bootstrap class files
-extdirs <dirs> Override location of installed extensions
-d <directory> Specify where to place generated class files
-encoding <encoding> Specify character encoding used by source files
-source <release> Provide source compatibility with specified release
-target <release> Generate class files for specific VM version
-help Print a synopsis of standard options打:C:\Documents and Settings\-1>java C:\Program Files\Java\HelloWorld.java
显示:Exception in thread "main" java.lang.NoClassDefFoundError: C:\Program
开始->运行->输入CMD
->输入 set path="你所安装JDK的BIN目录路径"
回车即可
再点javac HelloWorld.java
main() 方法要放到 public 类里面 就是 public class HelloWorld{}
配置上没问题` 因为有;%JAVA_HOME%\bin
path:%java_home%\bin;
classpath: .;%java_home%\dt.jar;%java_home%\tools.jar
注意:classpath前有点分号。
java_home: c:\program files\java\jdk1.5.06
path:%java_home%\bin;
classpath: .;%java_home%\lib\dt.jar;%java_home%\lib\tools.jar
注意:classpath前有点分号。