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<TITLE>Performing Bitwise Operations on a Bit Vector
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<h3>
e363.
Performing Bitwise Operations on a Bit Vector</h3>
The <code>BitSet</code> class implements a bit-vector of an arbitrary size.
It automatically grows dynamically. This example demonstrates how to
create and use a <code>BitSet</code>.
<P> The <code>BigInteger</code> class also support bitwise operations (see
<a href="../java.math/Bits.html" class="eglink"><font size="-1"><b>e129</b> Performing Bitwise Operations with BigInteger</font></a>). However, a <code>BigInteger</code> object is
immutable where a <code>BitSet</code> is mutable.
<pre>
// Create the bitset
BitSet bits = new BitSet();
// Set a bit on
bits.set(<font color="#0066ff"><i>2</i></font>); // 100 = decimal 4
// Retrieving the value of a bit
boolean b = bits.get(<font color="#0066ff"><i>0</i></font>); // false
b = bits.get(<font color="#0066ff"><i>2</i></font>); // true
// Clear a bit
bits.clear(<font color="#0066ff"><i>1</i></font>);
// Setting a range of bits
BitSet bits2 = new BitSet();
bits2.set(<font color="#0066ff"><i>1</i></font>, <font color="#0066ff"><i>4</i></font>); // 1110
// And'ing two bitsets
bits.and(bits2); // 0100
// Xor'ing two bitsets
bits.xor(bits2); // 1010
// Flip all bits in the bitset
bits.flip(0, bits.length()); // 0101
// Andnot'ing two bitsets
bits.andNot(bits2); // 0001
// Or'ing two bitsets
bits.or(bits2); // 1111
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Related Examples
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e364. <a class="eglink" href="Bits2Array.html?l=rel">
Converting Between a BitSet and a Byte Array
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See also:
<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Arrays">
Arrays
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Collections
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Dates
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Sets
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<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Sorted%20Collections">
Sorted Collections
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<a class="eglink" href="/egs/java.util/pkg.html?l=rel#Time">
Time
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