Junit + getResourceAsStream Returning Null

问题

Not sure how this is possible. I re-read up on getResourceAsStream and it's always returning null.

InputStream source = this.getClass().getResourceAsStream("test.xml");

Right next to test.java in the Finder (using OS X and Eclipse) is test.xml

I can open it in TextWrangler and view it as existing with data inside.

This is a Junit test if it makes any difference. I went and looked at existing Junit tests on our system and I'm using it in the exactly same manner as a working example (as in where the file is located and the code itself).

What small difference could there be preventing I assume getClass() from returning the right path?

Thanks!

回答1:

getResourceAsStream() is using the CLASSPATH, and as such it will load from wherever your classes are, not your source files.

I suspect you need to copy your XML to the same directory as your .class file.

回答2:

It's not finding the resource on the classpath. If you are using junit and maven make sure the resources are copied on the target/test-classes by adding <include> file directive on <testResource> section

You can also find out the location of your class in the file system by using

this.getClass().getResource(".")

and checking to see if the resource is there

回答3:

In case you are using Maven, add this part to your pom.xml

<build>
    <testResources>
        <testResource>
            <directory>${project.basedir}/src/test/resources</directory>
        </testResource>
    </testResources>
</build>

Your test.xml and other resource files must be located in src/test/resources

回答4:

I always have problem with this method. Here are 2 links, which might be useful:

Describes diference between getClass().getResource(); and getClass().getClassLoader().getResource();
Simple utility which simplifies these 2 approaches

I always experiment with adding "/" at the beginning or "./".

From my experience the best method is using FileInputStream. There is only one thing to remember (while using FileInputStream with Eclipse), with default settings, your working directory is set to projects root. You can always check where is your current directory (and what relative paths you need)using this piece of code.

回答5:

Assuming test.xml is located right under your test root source folder, do this:-

InputStream source = this.getClass().getClassLoader().getResourceAsStream("test.xml");

回答6:

I spent lot of time in this problem and it was missing me the following configuration: Right-click on an eclipse project and select Properties -> Java Build Path -> Source and edit Included row and add *.properties (*.fileExtension)

回答7:

Try MyClass.getResourceAsStream().

Also try putting the test.xml in your classpath. For instance, in an Eclipse web project put text.xml in webcontent/WEB-INF/classes

回答8:

From Java API:

http://docs.oracle.com/javase/6/docs/api/java/lang/ClassLoader.html#getSystemResource(java.lang.String)

Find a resource of the specified name from the search path used to load classes. This method locates the resource through the system class loader

So the syntax will for instance be: ClassLoader.getSystemResource("test.xml").toString();

Works like a charm!

回答9:

Put test.xml in the src/main/resources (or src/test/resources).

File file = ResourceUtils.getFile("classpath:test.xml");
String test = new String(Files.readAllBytes(file.toPath()));

回答10:

Add the folder that your having your resource files in to the source folders of eclipse. Then the file should be automatically put in the bin directory.

回答11:

I had this problem with a Spring class. System.class.getResourceAsStream(...) worked in unit tests but not in Tomcat, Thread.currentThread().getContextClassLoader().getResourceAsStream(...) worked in Tomcat but not in unit tests.

Ulitimately I went with:

ClassUtils.getDefaultClassLoader()
    .getResourceAsStream("com/example/mail/templates/invoice-past-due.html"))

I also found that once I did it this way, I did not need to have the path starting with a slash.

回答12:

You need to put the copy of your resource file to the test resources, in my example it is font file:

Then call next from your jUnit test:

 public static InputStream getFontAsStream() throws IOException {
        return Thread.currentThread().getContextClassLoader()
                    .getResourceAsStream("fonts/" + "FreeSans.ttf");
    }

来源：https://stackoverflow.com/questions/5238048/junit-getresourceasstream-returning-null

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java

getresource