March 25, 2025
November 13, 2022
Adler32 (Java SE 23 & JDK 23) in Java with Examples.
You will find code samples for most of the Adler32 methods.
Summary
A class that can be used to compute the Adler-32 checksum of a data stream. An Adler-32 checksum is almost as reliable as a CRC-32 but can be computed much faster.
final byte[] b = "abcd".getBytes();
System.out.println(Arrays.toString(b)); // [97, 98, 99, 100]
final var checksum = new Adler32();
checksum.update(b);
System.out.printf("%x%n", checksum.getValue()); // 3d8018b
Constructors
Adler32 ()
Creates a new Adler32 object.
final var checksum = new Adler32();
System.out.printf("%x%n", checksum.getValue()); // 1
checksum.update(123);
System.out.printf("%x%n", checksum.getValue()); // 7c007c
Methods
long getValue ()
Returns the checksum value.
final var b = "abcd".getBytes();
System.out.println(Arrays.toString(b)); // [97, 98, 99, 100]
final var checksum = new Adler32();
checksum.update(b);
System.out.printf("%x%n", checksum.getValue()); // 3d8018b
final var checksum = new Adler32();
checksum.update(97);
System.out.printf("%x%n", checksum.getValue()); // 620062
checksum.update(98);
System.out.printf("%x%n", checksum.getValue()); // 12600c4
checksum.update(99);
System.out.printf("%x%n", checksum.getValue()); // 24d0127
checksum.update(100);
System.out.printf("%x%n", checksum.getValue()); // 3d8018b
void reset ()
Resets the checksum to initial value.
final var checksum = new Adler32();
System.out.printf("%x%n", checksum.getValue()); // 1
checksum.update("abcd".getBytes());
System.out.printf("%x%n", checksum.getValue()); // 3d8018b
checksum.reset();
System.out.printf("%x%n", checksum.getValue()); // 1
void update (byte[] b, int off, int len)
Updates the checksum with the specified array of bytes.
final var b = "abcdXYZ".getBytes();
System.out.println(Arrays.toString(b)); // [97, 98, 99, 100, 88, 89, 90]
final var checksum = new Adler32();
checksum.update(b, 0, 4);
System.out.printf("%x%n", checksum.getValue()); // 3d8018b
checksum.reset();
checksum.update(b, 4, 3);
System.out.printf("%x%n", checksum.getValue()); // 217010c
final var checksum = new Adler32();
checksum.update("abcd".getBytes());
System.out.printf("%x%n", checksum.getValue()); // 3d8018b
checksum.reset();
checksum.update("XYZ".getBytes());
System.out.printf("%x%n", checksum.getValue()); // 217010c
void update (int b)
Updates the checksum with the specified byte (the low eight bits of the argument b).
final var b = "abcd".getBytes();
System.out.println(Arrays.toString(b)); // [97, 98, 99, 100]
final var checksum = new Adler32();
checksum.update(b);
System.out.printf("%x%n", checksum.getValue()); // 3d8018b
final var checksum = new Adler32();
checksum.update(97);
System.out.printf("%x%n", checksum.getValue()); // 620062
checksum.update(98);
System.out.printf("%x%n", checksum.getValue()); // 12600c4
checksum.update(99);
System.out.printf("%x%n", checksum.getValue()); // 24d0127
checksum.update(100);
System.out.printf("%x%n", checksum.getValue()); // 3d8018b
void update (ByteBuffer buffer)
Updates the checksum with the bytes from the specified buffer.
final var buffer = ByteBuffer.wrap("abcd".getBytes());
System.out.println(buffer); // java.nio.HeapByteBuffer[pos=0 lim=4 cap=4]
final var checksum = new Adler32();
checksum.update(buffer);
System.out.printf("%x%n", checksum.getValue()); // 3d8018b
System.out.println(buffer); // java.nio.HeapByteBuffer[pos=4 lim=4 cap=4]