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A Java library for collating textual sources, for example, to produce an apparatus.

There is a newer version: 1.7.1

package eu.interedition.collatex.suffixarray;

/**
 * An adapter for constructing suffix arrays on character sequences.
 *
 * @author Michał Nowak (Carrot Search)
 * @author Dawid Weiss (Carrot Search)
 * @see SuffixArrays#create(CharSequence)
 * @see SuffixArrays#create(CharSequence, ISuffixArrayBuilder)
 */
final class CharSequenceAdapter {
    private final ISuffixArrayBuilder delegate;

    /**
     * Last mapped input in {@link #buildSuffixArray(CharSequence)}.
     */
    int[] input;

    /**
     * Construct an adapter with a given underlying suffix array construction strategy.
     * The suffix array builder should accept non-negative characters, with a possibly
     * large alphabet size.
     *
     * @see DensePositiveDecorator
     */
    public CharSequenceAdapter(ISuffixArrayBuilder builder) {
        this.delegate = builder;
    }

    /**
     * Construct a suffix array for a given character sequence.
     */
    public int[] buildSuffixArray(CharSequence sequence) {
        /*
         * Allocate slightly more space, some suffix construction strategies need it and
         * we don't want to waste space for multiple symbol mappings.
         */

        this.input = new int[sequence.length() + SuffixArrays.MAX_EXTRA_TRAILING_SPACE];
        for (int i = sequence.length() - 1; i >= 0; i--) {
            input[i] = sequence.charAt(i);
        }

        final int start = 0;
        final int length = sequence.length();

        final ISymbolMapper mapper = new DensePositiveMapper(input, start, length);
        mapper.map(input, start, length);

        return delegate.buildSuffixArray(input, start, length);
    }
}