How to use Deflater in java.util.zip

Question

Hi i'm new to java and i'm trying to compress a byte stream using Deflater in java.util.zip .I followed an example from Oracle site .

try {
         // Encode a String into bytes
         String inputString = "blahblahblah";
         byte[] input = inputString.getBytes("UTF-8");

         // Compress the bytes
         byte[] output = new byte[100];
         Deflater compresser = new Deflater();

         compresser.setInput(input);
         compresser.finish();
         int compressedDataLength = compresser.deflate(output);
         compresser.end();

         // Decompress the bytes
         Inflater decompresser = new Inflater();
         decompresser.setInput(output, 0, compressedDataLength);
         byte[] result = new byte[100];
         int resultLength = decompresser.inflate(result);
         decompresser.end();

         // Decode the bytes into a String
         String outputString = new String(result, 0, resultLength, "UTF-8");
     } catch(java.io.UnsupportedEncodingException ex) {
         // handle
     } catch (java.util.zip.DataFormatException ex) {
         // handle
     }

When I run this code it gives me an error saying setInput() , finish() , deflate() and end() is not defined. Here is the error message

Exception in thread "main" java.lang.Error: Unresolved compilation problems: 
The method setInput(byte[]) is undefined for the type Deflater
The method finish() is undefined for the type Deflater
The method deflate(byte[]) is undefined for the type Deflater
The method end() is undefined for the type Deflater

at Deflater.main(Deflater.java:16)

I imported java.util.zip and looked in the Documentation in Oracle site.It says those methods exist.

Can't figure out where the problem is. Can someone help.

Answer 1

The problem is you are calling your main class Deflater , which is ambiguous for the compiler. There are two classes with the same name, your class and the Zip Deflater . You should change this line: Deflater compresser = new Deflater(); to this java.util.zip.Deflater compresser = new java.util.zip.Deflater(); or simply change the name of your main class.