Compiler

Introduction

The Java Compiler class is provided to support Java-to-native-code compilers and related services. By design, it serves as a placeholder for a JIT compiler implementation.

Note − This API is deprecated since Java 9 and is not available Java 21 onwards.

Class Declaration

Following is the declaration for java.lang.Compiler class −

publicfinalclassCompilerextendsObject

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Class methods

Sr.No.	Method & Description
1	static Object command(Object any)This method examines the argument type and its fields and perform some documented operation.
2	static boolean compileClass(Class<?> clazz)This method compiles the specified class.
3	static void disable()This method causes the Compiler to cease operation.
4	static boolean compileClasses(String string)This method compiles all classes whose name matches the specified string..
5	static void enable()This method cause the Compiler to resume operation.

Methods inherited

This class inherits methods from the following classes −

java.lang.Object

Enabling a Compiler Example

The following example shows the usage of java.lang.Compiler.enable() method. In this program, we’ve enabled the compiler using enable() method. Then prepare a compile command using command() method. Then we’ve retrieved hashcode of a new Integer object created and printed the same.

packagecom.tutorialspoint;publicclassCompilerDemo{publicstaticvoidmain(String[] args){// checking if compiler is enabled or not        Compiler.enable();System.out.println("Compiler Enabled...");Compiler.command("{java.lang.Integer.*}(compile)");Integer i =newInteger("50");// returns a hash code valueint retval = i.hashCode();System.out.println("Value = "+ retval);}}

Output

Let us compile and run the above program, this will produce the following result −

Compiler Enabled...
Value = 50