java - PrintStream vs PrintWriter -


i have searched site , have found answers, i'm having trouble understanding difference between these 2 classes. can explain differences between these 2 classes?

printstream original bridge deal encoding characters , other datatypes. if @ javadoc java.io.outputstream you'll see methods writing 2 distinct data types: byte , int.

in versions of jdk (1.0.x), when wanted write characters, 1 of 2 things, write bytes output stream (which assumed in system default character set):

outputstream.write("foobar".getbytes());

or wrap outputstream in printstream

printstream printstream = new printstream(outputstream); printstream.write("foobar");

see difference? printstream handling character conversion bytes, encoding (the constructor call above uses system default encoding, pass parameter). provides convenience methods writing double, boolean, etc....

in fact system.out , system.err defined printstream instances.

along comes jdk 1.1, , realize need better way deal pure character data, since printstream still has byte based methods writing. introduced "writer" abstract class deal strictly character, string , int data.

printwriter adds methods other types double, boolean, etc...

nowadays printwriter has format()/printf() methods format printing, etc...

as general rule, if you're writing character data, use writer instances. if you're writing binary (or mixed) data use outputstream instances.


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