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I have placed a java file and compiled it with out a main method in JRE/lib/ext directory. I want to access the file from a local Java file with out even mentioning about importing it in java. 

C:\Program Files\Java\jre1.8.0_60\lib\ext>cat TestClass.java
class TestClass
{
        public void displayMessage()
        {
                System.out.println("Hello World of Trials");
        }
}

C:\Program Files\Java\jre1.8.0_60\lib\ext>javac TestClass.java

C:\Program Files\Java\jre1.8.0_60\lib\ext>ls -lrt TestClass.*
-rwxrwxr--+ 1 Madhuri        None 103 Jun 17 12:23 TestClass.java
-rwxrwx---+ 1 Administrators None 418 Jun 17 12:25 TestClass.class

C:\Program Files\Java\jre1.8.0_60\lib\ext>



C:\Users\Madhuri\Documents>cat TestArt.java
class TestArt
{
        public static void main(String args[])
        {
                TestClass tc = new TestClass();
                tc.displayMessage();
        }
}

C:\Users\Madhuri\Documents>javac TestArt.java
TestArt.java:5: error: cannot find symbol
                TestClass tc = new TestClass();
                ^
  symbol:   class TestClass
  location: class TestArt
TestArt.java:5: error: cannot find symbol
                TestClass tc = new TestClass();
                                   ^
  symbol:   class TestClass
  location: class TestArt
2 errors

C:\Users\Madhuri\Documents>

Flow of class loading for a simple program

From the above answer, i thought it would be possible. I tried compiling with verbose option and understood it only accepts JAR files. 

C:\Users\Madhuri\Documents>javac -verbose TestArt.java
[parsing started RegularFileObject[TestArt.java]]
[parsing completed 37ms]
[search path for source files: .]
[search path for class files: C:\Program Files\Java\jdk1.8.0_60\jre\lib\resources.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\rt.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\sunrsasign.jar,C:\Program Files\Java\jdk1.8.0_60
jre\lib\jsse.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\jce.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\charsets.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\jfr.jar,C:\Program Files\Java\jdk1.8.0_60\jre\classes,C:\Prog
am Files\Java\jdk1.8.0_60\jre\lib\ext\access-bridge-64.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ext\cldrdata.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ext\dnsns.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ext\jacce
s.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ext\jfxrt.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ext\localedata.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ext\nashorn.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ex
\sunec.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ext\sunjce_provider.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ext\sunmscapi.jar,C:\Program Files\Java\jdk1.8.0_60\jre\lib\ext\sunpkcs11.jar,C:\Program Files\Java\jdk1.8
0_60\jre\lib\ext\zipfs.jar,.]
[loading ZipFileIndexFileObject[C:\Program Files\Java\jdk1.8.0_60\lib\ct.sym(META-INF/sym/rt.jar/java/lang/Object.class)]]
[loading ZipFileIndexFileObject[C:\Program Files\Java\jdk1.8.0_60\lib\ct.sym(META-INF/sym/rt.jar/java/lang/String.class)]]
[checking TestArt]
[loading ZipFileIndexFileObject[C:\Program Files\Java\jdk1.8.0_60\lib\ct.sym(META-INF/sym/rt.jar/java/io/Serializable.class)]]
[loading ZipFileIndexFileObject[C:\Program Files\Java\jdk1.8.0_60\lib\ct.sym(META-INF/sym/rt.jar/java/lang/AutoCloseable.class)]]
TestArt.java:5: error: cannot find symbol
                TestClass tc = new TestClass();
                ^
  symbol:   class TestClass
  location: class TestArt
TestArt.java:5: error: cannot find symbol
                TestClass tc = new TestClass();
                                   ^
  symbol:   class TestClass
  location: class TestArt
[total 570ms]
2 errors

C:\Users\Madhuri\Documents>

Do i need to create a JAR file in ext dir to load it automatically or else is there any way to load a class file directly by the program ??

Community
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Mallesh
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    This may be an X/Y Problem. Could you describe why you want to hide the import and make it seem like your class was belonging to the JRE? – Fildor Jun 17 '16 at 07:22
  • 2
    See: [The Extension Mechanism](https://docs.oracle.com/javase/tutorial/ext/). Jars put in `jre/lib/ext` are automatically added to the classpath. But this is not the "normal" way to add jars to the classpath, so I do not recommend using this mechanism. The problem with it is that those jars will be added to **all** Java programs running on your computer, and that's not a good idea. Instead, just make sure the jar you need is in the classpath when running your application. – Jesper Jun 17 '16 at 07:24
  • I want to create some default methods in java to simplify my tasks and i want them to available to all my programs. – Mallesh Jun 18 '16 at 02:44
  • @Jesper As you said, May be it is not a recommended mechanism. But i want to give it a try to my thought whether it is possible or not. – Mallesh Jun 18 '16 at 02:50

1 Answers1

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It is not possible of accessing the class from a local Java file without importing it in java. Even if you copy that java file in JRE/lib/ext directory which you want to access in other class, it does not mean that required class would not get added to default class path.

san544
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