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56 to 60 Java Questions

56. What is the purpose of apache tomcat?
Apache server is a standalone server that is used to test servlets and create JSP pages. It is free and open source that is integrated in the Apache web server. It is fast, reliable server to configure the applications but it is hard to install. It is a servlet container that includes tools to configure and manage the server to run the applications. It can also be configured by editing XML configuration files.

57. Where pragma is used?
Pragma is used inside the servlets in the header with a certain value. The value is of no-cache that tells that a servlets is acting as a proxy and it has to forward request. Pragma directives allow the compiler to use machine and operating system features while keeping the overall functionality with the Java language. These are different for different compilers.

58. Briefly explain daemon thread.
Daemon thread is a low priority thread which runs in the background performs garbage collection operation for the java runtime system.

59. What is a native method?
A native method is a method that is implemented in a language other than Java.

60. Explain different way of using thread?
A Java thread could be implemented by using Runnable interface or by extending the Thread class. The Runnable is more advantageous, when you are going for multiple inheritance.

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