Where is the org.junit.contrib.java.lang.system.StandardOutputStreamLog?

SystemOutRule superseded StandardOutputStreamLog as suggested by @Rahul Tripathi.

Just adding few more pointers to get started right away.

Maven dependency:

<dependency>
    <groupId>com.github.stefanbirkner</groupId>
    <artifactId>system-rules</artifactId>
    <version>1.18.0</version>
    <scope>test</scope>
</dependency>

Add the jar to the buildpath to get the below import.

import org.junit.contrib.java.lang.system.SystemOutRule;

public void MyTest {
    @Rule
    public final SystemOutRule systemOutRule = new SystemOutRule().enableLog();

    @Test
    public void writesTextToSystemOut() {
        System.out.print("hello world");
        assertEquals("hello world", systemOutRule.getLog());
    }
}

Reference: http://stefanbirkner.github.io/system-rules/

This class is deprecated and you should use SystemOutRule.

Check the source

StandardOutputStreamLog()

Deprecated.

Please use new SystemOutRule().enableLog().

Creates a rule that records writes while they are still written to the standard output stream.

StandardOutputStreamLog() is not deprecated. It's a class that's not present in the JUnit 4.x package. I google this class plus the word maven like so : org.junit.contrib.java.lang.system.StandardOutputStreamLog() + maven and I found that it is not define in the junit Maven Repository but instead in the com.github.stefanbirkner. So by adding the maven coordinate

<dependency>
    <groupId>com.github.stefanbirkner</groupId>
    <artifactId>system-rules</artifactId>
    <version>1.16.0</version>
</dependency>

You should be able to resolve the problem.