Java Tools - Java Compiler

C:\>javac

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
used
-classpath<path> Specify where to find user class files and
annotation processors

-cp <path> Specify where to find user class files and
annotation processors

 -sourcepath<path> Specify where to find input source files

 -bootclasspath<path> Override location of bootstrap class files
-extdirs<dirs> Override location of installed extensions
-endorseddirs<dirs> Override location of endorsed standards path

-proc:{none,only} Control whether annotation processing and/or
compilation is done.

 -processor <class1>[,<class2>,<class3>...]
Names of the annotation processors to run;
bypasses default discovery process

 -processorpath<path> Specify where to find annotation processors
-d <directory> Specify where to place generated class files
-s <directory> Specify where to place generated source files
-implicit:{none,class} Specify whether or not to generate class files
for implicitly referenced 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
-version Version information
-help Print a synopsis of standard options
-Akey[=value] Options to pass to annotation processors
-X Print a synopsis of nonstandard options
-J<flag> Pass <flag> directly to the runtime system

C:\>

class A{
public static void main(String[] args){
int a;
int b=2;
int c=a+b;
System.out.println(c);
}
}

C:\Program Files\Java\jdk1.6.0_01\bin>javac A.java
A.java:6: variable a might not have been initialized
int c=a+b;
^
1 error

C:\Program Files\Java\jdk1.6.0_01\bin>

class A{
public static void main(String[] args) {
int a=2;
int b=2;
int c=a+b;
System.out.println(c);
}
}

C:\Program Files\Java\jdk1.6.0_01\bin>javac A.java

C:\Program Files\Java\jdk1.6.0_01\bin>java A
4