Java: split() method with pipe special character

I have a String = "Hello-new-World". And when i use the split() method with different regex values, it acts differently.

String str = "Hello-new-world"
String[] strbuf=str.split("-");
for(int i=0;i<strbuf.length;i++)
 System.out.print(strbuf[i]+" ");

The output i get is :

hello
new
world

whereas if i change my string to "Hello|new|world", i get an altogether different answer. The new output becomes:

h
e
l
l
o
|
n
e
w
|
w
o
r
l
d

Can someone please explain what could be the possible reason for this.