4.0.0 com.googlecode.javaewah JavaEWAH 0.5.6 jar 1.5 1.5 UTF-8 Apache 2 http://www.apache.org/licenses/LICENSE-2.0.txt repo A business-friendly OSS license scm:git:git@github.com:lemire/javaewah.git scm:git:git@github.com:lemire/javaewah.git scm:git:git@github.com:lemire/javaewah.git lemire Daniel Lemire lemire@gmail.com http://lemire.me/en/ LICEF Research Center http://licef.ca architect developer maintainer -5 http://lemire.me/fr/images/JPG/profile2011B_152.jpg junit junit 4.10 test Google Code Issue Tracking http://code.google.com/p/javaewah/issues/list org.sonatype.oss oss-parent 5 org.apache.maven.plugins maven-gpg-plugin 1.4 sign-artifacts verify sign org.apache.maven.plugins maven-javadoc-plugin 2.8 attach-javadocs jar org.apache.maven.plugins maven-source-plugin 2.1.2 attach-sources jar JavaEWAH http://code.google.com/p/javaewah/ The bit array data structure is implemented in Java as the BitSet class. Unfortunately, this fails to scale without compression. JavaEWAH is a word-aligned compressed variant of the Java bitset class. It uses a 64-bit run-length encoding (RLE) compression scheme. The goal of word-aligned compression is not to achieve the best compression, but rather to improve query processing time. Hence, we try to save CPU cycles, maybe at the expense of storage. However, the EWAH scheme we implemented is always more efficient storage-wise than an uncompressed bitmap (implemented in Java as the BitSet class). Unlike some alternatives, javaewah does not rely on a patented scheme.