COMPILER API

com.sun.javac.tools.javac
  before1.6 the compiler api was contained in package above

javax.tools.*

* compile a the class Test.java writing errors to a file
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
FileOutputStream errorStream = new FileOutputStream("Errors.txt");
int compilationResult = compiler.run(null, null, errorStream, "Test.java");

* compile 2 files
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
compiler.run(null, null, null, “One.java”, “Two.java”);

* pass options to the java compiler with c.run()
>> compiler.run(null, null, null, ”-classpath”, ”PathToClasses”, ”-sourcepath”, ”PathToSources”, ”One.java”, ”Two.java”);

* compile with a diagnostic listener
------------------------------
AdvancedCompilationTest.java:
package test;
import java.io.*;
import java.util.*;
import javax.tools.*;
import javax.tools.JavaCompiler.*;
public class AdvancedCompilationTest {
	public static void main(String[] args) throws Exception {
		JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
// Line 1.
		MyDiagnosticListener listener = new MyDiagnosticListener(); // Line 2.
		StandardJavaFileManager fileManager  =
		compiler.getStandardFileManager(listener, null, null); // Line 3.
String fileToCompile = "test" + File.separator + "ManyErrors.java";
// Line 4
		Iterable fileObjects =						fileManager.getJavaFileObjectsFromStrings(
Arrays.asList(fileToCompile));  // Line 5
CompilationTask task = compiler.getTask(null, fileManager, listener, null, null, fileObjects); // Line 6
		Boolean result = task.call(); // Line 7
		if(result == true){
			System.out.println("Compilation has succeeded");
		}
	}
}
class MyDiagnosticListener implements DiagnosticListener{
	public void report(Diagnostic diagnostic) {
		System.out.println("Code->" +  diagnostic.getCode());
		System.out.println("Column Number->" + diagnostic.getColumnNumber());
		System.out.println("End Position->" + diagnostic.getEndPosition());
		System.out.println("Kind->" + diagnostic.getKind());
		System.out.println("Line Number->" + diagnostic.getLineNumber());
		System.out.println("Message->"+ diagnostic.getMessage(Locale.ENGLISH));
		System.out.println("Position->" + diagnostic.getPosition());
		System.out.println("Source" + diagnostic.getSource());
		System.out.println("Start Position->" + diagnostic.getStartPosition());
		System.out.println("\n");
	}
}
,,,
VARARGS 

* call a vararg method with an array. its ok
>> addNumbers(new int[]{10, 34, 54});


*a vararg function definition
------------------------------------
public int addNumbers(int …numbers){

int total = 0;
For(int temp : numbers){
	Total = total + temp;
}
return total;
},,,