Reading Properties file in Java

java properties
nikos picture nikos · Nov 27, 2011 · Viewed 366.8k times · Source

I have the following code trying to read a properties file:

Properties prop = new Properties();
ClassLoader loader = Thread.currentThread().getContextClassLoader();           
InputStream stream = loader.getResourceAsStream("myProp.properties");
prop.load(stream);

I get an exception at the last line. Specifically:

Exception in thread "main" java.lang.NullPointerException
at java.util.Properties$LineReader.readLine(Properties.java:418)
at java.util.Properties.load0(Properties.java:337)
at java.util.Properties.load(Properties.java:325)
at Assignment1.BaseStation.readPropertyFile(BaseStation.java:46)
at Assignment1.BaseStation.main(BaseStation.java:87)

thanks, Nikos

Answer

Mark Elliot picture Mark Elliot · Nov 27, 2011

Based on your exception, the InputStream is null, this means the class loader is not finding your properties file. I'm guessing that myProp.properties is in the root of your project, if that's the case, you need a preceding slash:

InputStream stream = loader.getResourceAsStream("/myProp.properties");

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