getServletConfig() / getServletContext() returning null value

java servlets servletconfig
display4 picture display4 · Oct 22, 2014 · Viewed 11.1k times · Source

I want to get servletContext in a Java class to read a file from WEB-INF directory. I extended my class with HttpServlet and tried to get the context as in the below code, but the servlet config is returned as null. I don't use any jsp or controller. My intention is to read a file directly placed in the WEB-INF directory from a Java class. Please let me know how I can get not null servletConfig / servletContext in the class:

ServletConfig config = getServletConfig(); 
ServletContext context = config.getServletContext(); 
InputStream resourceContent = context.getResourceAsStream("/WEB-INF/samplefile");

Answer

user207421 picture user207421 · Oct 22, 2014

Trap for young players. If you override the

public void init(ServletConfig config)

method, you must call

super.init(config);

inside the method. Otherwise the superclass sees the context as null. It's mentioned in the Javadoc:

When overriding this form of the method, call super.init(config).

NB You can get the context directly via getServletContext(). There's no need to go via getServletConfig().

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