类似的错误有一天，在我的情况下，我不得不手工解开一些Java *。pack 文件。

I had similar error one day and in my case I had to unpack some Java *.pack files by hand.

$ find . -type f -name '*.pack'  
./jre/lib/charsets.pack          
./jre/lib/deploy.pack            
./jre/lib/ext/jfxrt.pack         
./jre/lib/ext/localedata.pack    
./jre/lib/javaws.pack            
./jre/lib/jsse.pack              
./jre/lib/plugin.pack            
./jre/lib/rt.pack                
./lib/tools.pack

每个文件必须解压缩，如 unpack200.exe jsse.pack jsse.jar ，然后问题SHA1算法不可用类路径。

Each file had to be unpacked like unpack200.exe jsse.pack jsse.jar and then problem with "The SHA1 algorithm is not available in your classpath" was solved.