Java Binary Block Parser (JBBP) unsigned int 32 parser

Uint32.java

import com.igormaznitsa.jbbp.JBBPCustomFieldTypeProcessor;
import com.igormaznitsa.jbbp.compiler.JBBPNamedFieldInfo;
import com.igormaznitsa.jbbp.compiler.tokenizer.JBBPFieldTypeParameterContainer;
import com.igormaznitsa.jbbp.io.JBBPBitInputStream;
import com.igormaznitsa.jbbp.io.JBBPBitOrder;
import com.igormaznitsa.jbbp.io.JBBPByteOrder;
import com.igormaznitsa.jbbp.model.*;

import java.io.EOFException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/**
 * A custom processor for Java Binary Block Parser (JBBP)
 * to read unsigned int 32 bytes (uint32) and return them as longs
 *
 * @author alastair.mccormack 
 */

public final class Uint32 implements JBBPCustomFieldTypeProcessor {

    private static final String[] TYPES = new String[]{"uint32"};

    private static long uint32_read(final JBBPBitInputStream in, final JBBPByteOrder byteOrder, final JBBPBitOrder bitOrder) throws IOException {
        final int signedInt = in.readInt(byteOrder);

        /* Java 8
        return Integer.toUnsignedLong(signedInt);*/

        // Java *
        return signedInt & 0xffffffffL;
    }

    @Override
    public String[] getCustomFieldTypes() {
        return TYPES;
    }

    @Override
    public boolean isAllowed(final JBBPFieldTypeParameterContainer fieldType, final String fieldName, final int extraData, final boolean isArray) {
        return extraData == 0;
    }

    /**
     * Converts List of Longs to long[]
     *
     * @param longs A List of Longs
     * @return
     */
    private long[] convertLongs(List<Long> longs)
    {
        long[] ret = new long[longs.size()];
        Iterator<Long> iterator = longs.iterator();
        for (int i = 0; i < ret.length; i++)
        {
            ret[i] = iterator.next().longValue();
        }
        return ret;
    }

    @Override
    public JBBPAbstractField readCustomFieldType(final JBBPBitInputStream in, final JBBPBitOrder bitOrder,
                                                 final int parserFlags, final JBBPFieldTypeParameterContainer customTypeFieldInfo,
                                                 final JBBPNamedFieldInfo fieldName, final int extraData,
                                                 final boolean readWholeStream, final int arrayLength) throws IOException {
        // read just one
        if (arrayLength < 0) {
            final long uint32_val = uint32_read(in, customTypeFieldInfo.getByteOrder(), bitOrder);
            return new JBBPFieldLong(fieldName, uint32_val);
        } else {
        // read multiple

            // if [_] given
            if (readWholeStream) {
                // the Inner Circle
                ArrayList<Long> laLaLaLaLong = new ArrayList<Long>();

                // Read as much as possible
                try {
                    while (true) {
                        laLaLaLaLong.add(uint32_read(in, customTypeFieldInfo.getByteOrder(), bitOrder));
                    }
                } catch (EOFException e) {

                }

                long longs[] = convertLongs(laLaLaLaLong);

                return new JBBPFieldArrayLong(fieldName, longs);

            } else {
                // [n] given

                final long[] array = new long[arrayLength];
                for (int i = 0; i < arrayLength; i++) {
                    array[i] = uint32_read(in, customTypeFieldInfo.getByteOrder(), bitOrder);
                }
                return new JBBPFieldArrayLong(fieldName, array);
            }
        }
    }
}