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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2017 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.wildfly.common.iteration;

import java.util.NoSuchElementException;

import org.wildfly.common.Assert;
import org.wildfly.common.bytes.ByteStringBuilder;

/**
 */
final class Utf8EncodingByteIterator extends ByteIterator {
    private final CodePointIterator iter;
    private final boolean escapeNul;
    // state 0 = between code points
    // state 1 = after byte 1 of 2
    // state 2 = after byte 1 of 3
    // state 3 = after byte 2 of 3
    // state 4 = after byte 1 of 4
    // state 5 = after byte 2 of 4
    // state 6 = after byte 3 of 4

    private int st;
    private int cp;
    private long offset;

    Utf8EncodingByteIterator(final CodePointIterator iter, final boolean escapeNul) {
        this.iter = iter;
        this.escapeNul = escapeNul;
        cp = - 1;
    }

    public boolean hasNext() {
        return st != 0 || iter.hasNext();
    }

    public boolean hasPrevious() {
        return st != 0 || iter.hasPrevious();
    }

    public int next() throws NoSuchElementException {
        if (! hasNext()) throw new NoSuchElementException();
        offset++;
        switch (st) {
            case 0: {
                int cp = iter.next();
                if (cp == 0 && ! escapeNul || cp < 0x80) {
                    return cp;
                } else if (cp < 0x800) {
                    this.cp = cp;
                    st = 1;
                    return 0b110_00000 | cp >> 6;
                } else if (cp < 0x10000) {
                    this.cp = cp;
                    st = 2;
                    return 0b1110_0000 | cp >> 12;
                } else if (cp < 0x110000) {
                    this.cp = cp;
                    st = 4;
                    return 0b11110_000 | cp >> 18;
                } else {
                    this.cp = '�';
                    st = 2;
                    return 0b1110_0000 | '�' >> 12;
                }
            }
            case 1:
            case 3:
            case 6: {
                st = 0;
                return 0b10_000000 | cp & 0x3f;
            }
            case 2: {
                st = 3;
                return 0b10_000000 | cp >> 6 & 0x3f;
            }
            case 4: {
                st = 5;
                return 0b10_000000 | cp >> 12 & 0x3f;
            }
            case 5: {
                st = 6;
                return 0b10_000000 | cp >> 6 & 0x3f;
            }
            default: {
                throw Assert.impossibleSwitchCase(st);
            }
        }
    }

    public int peekNext() throws NoSuchElementException {
        if (! hasNext()) throw new NoSuchElementException();
        switch (st) {
            case 0: {
                int cp = iter.peekNext();
                if (cp < 0x80) {
                    return cp;
                } else if (cp < 0x800) {
                    return 0b110_00000 | cp >> 6;
                } else if (cp < 0x10000) {
                    return 0b1110_0000 | cp >> 12;
                } else if (cp < 0x110000) {
                    return 0b11110_000 | cp >> 18;
                } else {
                    return 0b1110_0000 | '�' >> 12;
                }
            }
            case 1:
            case 3:
            case 6: {
                return 0b10_000000 | cp & 0x3f;
            }
            case 2:
            case 5: {
                return 0b10_000000 | cp >> 6 & 0x3f;
            }
            case 4: {
                return 0b10_000000 | cp >> 12 & 0x3f;
            }
            default: {
                throw Assert.impossibleSwitchCase(st);
            }
        }
    }

    public int previous() throws NoSuchElementException {
        if (! hasPrevious()) throw new NoSuchElementException();
        offset--;
        switch (st) {
            case 0: {
                int cp = iter.previous();
                if (cp == 0 && ! escapeNul || cp < 0x80) {
                    return cp;
                } else if (cp < 0x800) {
                    this.cp = cp;
                    st = 1;
                    return 0b10_000000 | cp & 0x3f;
                } else if (cp < 0x10000) {
                    this.cp = cp;
                    st = 3;
                    return 0b10_000000 | cp & 0x3f;
                } else if (cp < 0x110000) {
                    this.cp = cp;
                    st = 6;
                    return 0b10_000000 | cp & 0x3f;
                } else {
                    this.cp = '�';
                    st = 3;
                    return 0b10_000000 | '�' & 0x3f;
                }
            }
            case 1: {
                st = 0;
                return 0b110_00000 | cp >> 6;
            }
            case 2: {
                st = 0;
                return 0b1110_0000 | cp >> 12;
            }
            case 3: {
                st = 2;
                return 0b10_000000 | cp >> 6 & 0x3f;
            }
            case 4: {
                st = 0;
                return 0b11110_000 | cp >> 18;
            }
            case 5: {
                st = 4;
                return 0b10_000000 | cp >> 12 & 0x3f;
            }
            case 6: {
                st = 5;
                return 0b10_000000 | cp >> 6 & 0x3f;
            }
            default: {
                throw Assert.impossibleSwitchCase(st);
            }
        }
    }

    public int peekPrevious() throws NoSuchElementException {
        if (! hasPrevious()) throw new NoSuchElementException();
        switch (st) {
            case 0: {
                int cp = iter.peekPrevious();
                if (cp == 0 && ! escapeNul || cp < 0x80) {
                    return cp;
                } else if (cp < 0x800) {
                    return 0b10_000000 | cp & 0x3f;
                } else if (cp < 0x10000) {
                    return 0b10_000000 | cp & 0x3f;
                } else if (cp < 0x110000) {
                    return 0b10_000000 | cp & 0x3f;
                } else {
                    return 0b10_000000 | '�' & 0x3f;
                }
            }
            case 1: {
                return 0b110_00000 | cp >> 6;
            }
            case 2: {
                return 0b1110_0000 | cp >> 12;
            }
            case 3:
            case 6: {
                return 0b10_000000 | cp >> 6 & 0x3f;
            }
            case 4: {
                return 0b11110_000 | cp >> 18;
            }
            case 5: {
                return 0b10_000000 | cp >> 12 & 0x3f;
            }
            default: {
                throw Assert.impossibleSwitchCase(st);
            }
        }
    }

    public ByteStringBuilder appendTo(final ByteStringBuilder builder) {
        if (st == 0) {
            // this is faster
            final int oldLen = builder.length();
            builder.appendUtf8(iter);
            offset += builder.length() - oldLen;
        } else {
            super.appendTo(builder);
        }
        return builder;
    }

    public long getIndex() {
        return offset;
    }
}




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