java - Why we can't extends more than one class -


this question has answer here:

well, developing application uses jframe , applet.

why can't extend both..

public class myclass extends applet, javax.swing.jframe {...} //invalid...

the valid code is.

public class myclass extends applet {     javax.swing.jframe frame = new javax.swing.jframe();     public void init(){         frame.setsize(300, 400);         frame.setvisible(true);     } }

why so? why can't extends more 1 class

the designers of java learned mistakes made in other languages such c++ diamond problem issue caused multiple inheritance decided make java single inheritance language simplify development.


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