Java: Conversion of String to byte array, then to long value and vice versa
Basically, I'm looking for .NET's BitConverter.
I need to get bytes from String, then parse them to long value and store it. After that, read long value, parse to byte array and create original String. How can I achieve this in J开发者_StackOverflow社区ava?
Edit: Someone did already ask similar question. I am looking more like for samples then javadoc reference ...
String
has a getBytes
method. You could use this to get a byte array.
To store the byte-array as longs, I suggest you wrap the byte-array in a ByteBuffer
and use the asLongBuffer
method.
To get the String
back from an array of bytes, you could use the String(byte[] bytes)
constructor.
String input = "hello long world";
byte[] bytes = input.getBytes();
LongBuffer tmpBuf = ByteBuffer.wrap(bytes).asLongBuffer();
long[] lArr = new long[tmpBuf.remaining()];
for (int i = 0; i < lArr.length; i++)
lArr[i] = tmpBuf.get();
System.out.println(input);
System.out.println(Arrays.toString(lArr));
// store longs...
// ...load longs
long[] longs = { 7522537965568945263L, 7955362964116237412L };
byte[] inputBytes = new byte[longs.length * 8];
ByteBuffer bbuf = ByteBuffer.wrap(inputBytes);
for (long l : longs)
bbuf.putLong(l);
System.out.println(new String(inputBytes));
Note that you probably want to store an extra integer telling how many bytes the long-array actually stores, since the number of bytes may not be a multiple of 8.
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