Hi, I can't find out what << means in java, because I can't search for it on Google I am absolutely lost!
The code in question is:
public int getRGB() {
return ((red << 16) | (green << 8) | blue);
}
taken from http://java.sun.com/docs/books/tutorial/essential/concurrency/example/ImmutableRGB.java
Would really appreciate someone telling me, thanks!
Left shift of the bits
If red == 4 (which in binary is: 00000100) then red << 16 will insert sixteen 0-bits at its right, yielding: 000001000000000000000000 which is 262144 in decimal
Left shift a number of bits. It is equivalent to multiplying by two that many times.
It's used for setting specific bits in a byte, or specific bytes in a word.
Q. What is this?
A. An "operator"
Q. How do I get to know about operators in java?
A. Google for "Java operators"
And the result is this:
The signed left shift operator "<<" shifts a bit pattern to the left, and the signed right shift operator ">>" shifts a bit pattern to the right. The bit pattern is given by the left-hand operand, and the number of positions to shift by the right-hand operand. The unsigned right shift operator ">>>" shifts a zero into the leftmost position, while the leftmost position after ">>" depends on sign extension.
It's the left-shift operator. If you google for those words, you'll get links like this one, explaining how to use it.
its a bit shift. search for operators java, it will return you detailed explanations.
It is the left shift operator. Here's some more information on shift operators from the Java Tutorial.
In your example code the three integer values: red, green and blue will typically have values 0-255. Hence, it is possible to combine these values and represent them as a single integer by shifting the red value by 16 bits, shifting the green value by 8 bits and then performing a bitwise-OR operation to combine the values.