title: java -jar: What's the default class path?
body: <p>In a jar file, <code>MANIFEST.mf</code> contains following line:</p>
  
  <p>style A:</p>
  
  <pre><code>Class-Path: .
  </code></pre>
  
  <p>style B:</p>
  
  <pre><code>Class-Path: . eric-java-util_lib/tomcat-api.jar
  </code></pre>
  
  <p>style C:</p>
  
  <pre><code>// No `Class-Path` specified.
  </code></pre>
  
  <p><strong>Questions:</strong></p>
  
  <ol>
  <li>In style B, is the jar specified by <code>Class-Path</code> related to residing dir of current jar?</li>
  <li>Then in style A and B, what does <code>.</code> mean? Is it uncompressed root dir of jar, or the residing dir of current jar? I guess it should be the later, but not sure.</li>
  <li>It seems classes &amp; packages besides <code>MANIFEST.mf</code> are also included in classpath in all the 3 styles, is it due to <code>.</code>? Or, the default classpath for <code>java -jar</code> is just the root dir of uncompress jar file?</li>
  </ol>