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devgianludevgianlu
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Fixed #94 
1 parent 623c108 commit fbdab16

9 files changed

Lines changed: 177 additions & 13 deletions

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‎common/src/main/java/xyz/gianlu/librespot/common/Base62.java‎

Lines changed: 165 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,165 @@
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package xyz.gianlu.librespot.common;
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import java.io.ByteArrayOutputStream;
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/**
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* A Base62 encoder/decoder.
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*
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* @author Sebastian Ruhleder, [email protected]
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*/
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public class Base62 {
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private static final int STANDARD_BASE = 256;
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private static final int TARGET_BASE = 62;
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private final byte[] alphabet;
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private byte[] lookup;
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private Base62(byte[] alphabet) {
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this.alphabet = alphabet;
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createLookupTable();
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}
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/**
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* Creates a {@link Base62} instance. Defaults to the GMP-style character set.
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*
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* @return a {@link Base62} instance.
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*/
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public static Base62 createInstance() {
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return createInstanceWithGmpCharacterSet();
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}
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/**
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* Creates a {@link Base62} instance using the GMP-style character set.
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*
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* @return a {@link Base62} instance.
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*/
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public static Base62 createInstanceWithGmpCharacterSet() {
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return new Base62(CharacterSets.GMP);
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}
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/**
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* Creates a {@link Base62} instance using the inverted character set.
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*
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* @return a {@link Base62} instance.
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*/
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public static Base62 createInstanceWithInvertedCharacterSet() {
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return new Base62(CharacterSets.INVERTED);
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}
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/**
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* Encodes a sequence of bytes in Base62 encoding.
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*
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* @param message a byte sequence.
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* @return a sequence of Base62-encoded bytes.
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*/
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public byte[] encode(byte[] message) {
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byte[] indices = convert(message, STANDARD_BASE, TARGET_BASE);
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return translate(indices, alphabet);
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}
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/**
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* Decodes a sequence of Base62-encoded bytes.
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*
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* @param encoded a sequence of Base62-encoded bytes.
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* @return a byte sequence.
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*/
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public byte[] decode(byte[] encoded) {
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byte[] prepared = translate(encoded, lookup);
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return convert(prepared, TARGET_BASE, STANDARD_BASE);
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}
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/**
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* Uses the elements of a byte array as indices to a dictionary and returns the corresponding values
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* in form of a byte array.
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*/
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private byte[] translate(byte[] indices, byte[] dictionary) {
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byte[] translation = new byte[indices.length];
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for (int i = 0; i < indices.length; i++)
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translation[i] = dictionary[indices[i]];
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return translation;
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}
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/**
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* Converts a byte array from a source base to a target base using the alphabet.
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*/
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private byte[] convert(byte[] message, int sourceBase, int targetBase) {
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// This algorithm is inspired by: http://codegolf.stackexchange.com/a/21672
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int estimatedLength = estimateOutputLength(message.length, sourceBase, targetBase);
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ByteArrayOutputStream out = new ByteArrayOutputStream(estimatedLength);
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byte[] source = message;
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while (source.length > 0) {
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ByteArrayOutputStream quotient = new ByteArrayOutputStream(source.length);
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int remainder = 0;
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for (byte b : source) {
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int accumulator = (b & 0xFF) + remainder * sourceBase;
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int digit = (accumulator - (accumulator % targetBase)) / targetBase;
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remainder = accumulator % targetBase;
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if (quotient.size() > 0 || digit > 0)
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quotient.write(digit);
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}
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out.write(remainder);
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source = quotient.toByteArray();
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}
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// pad output with zeroes corresponding to the number of leading zeroes in the message
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for (int i = 0; i < estimatedLength - out.size(); i++)
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out.write(0);
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return reverse(out.toByteArray());
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}
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/**
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* Estimates the length of the output in bytes.
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*/
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private int estimateOutputLength(int inputLength, int sourceBase, int targetBase) {
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return (int) Math.ceil((Math.log(sourceBase) / Math.log(targetBase)) * inputLength);
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}
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/**
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* Reverses a byte array.
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*/
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private byte[] reverse(byte[] arr) {
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int length = arr.length;
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byte[] reversed = new byte[length];
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for (int i = 0; i < length; i++)
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reversed[length - i - 1] = arr[i];
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return reversed;
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}
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/**
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* Creates the lookup table from character to index of character in character set.
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*/
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private void createLookupTable() {
137+
lookup = new byte[256];
138+
for (int i = 0; i < alphabet.length; i++)
139+
lookup[alphabet[i]] = (byte) (i & 0xFF);
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}
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private static class CharacterSets {
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private static final byte[] GMP = {
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(byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5', (byte) '6', (byte) '7',
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(byte) '8', (byte) '9', (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F',
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(byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N',
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(byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V',
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(byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd',
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(byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l',
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(byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't',
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(byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z'
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};
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private static final byte[] INVERTED = {
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(byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5', (byte) '6', (byte) '7',
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(byte) '8', (byte) '9', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f',
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(byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n',
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(byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u', (byte) 'v',
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(byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D',
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(byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L',
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(byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T',
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(byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z'
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};
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}
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}
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‎common/src/main/java/xyz/gianlu/librespot/common/Utils.java‎

Lines changed: 3 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -20,6 +20,7 @@
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import java.lang.reflect.Modifier;
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import java.math.BigInteger;
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import java.nio.ByteBuffer;
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import java.nio.charset.StandardCharsets;
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import java.security.Permission;
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import java.security.PermissionCollection;
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import java.util.Arrays;
@@ -47,7 +48,7 @@ public static String decodeGZip(@NotNull ByteString bytes) throws IOException {
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int count;
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while ((count = gzis.read(buffer)) != -1)
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dataOut.write(buffer, 0, count);
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return new String(dataOut.toByteArray(), "UTF-8");
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return new String(dataOut.toByteArray(), StandardCharsets.UTF_8);
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}
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}
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@@ -165,7 +166,7 @@ public static String[] split(@NotNull String str, char c) {
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if (i == -1) {
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split[j] = tmp;
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} else {
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split[j] = tmp.substring(i + 1, tmp.length());
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split[j] = tmp.substring(i + 1);
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tmp = tmp.substring(0, i);
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}
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}

‎core/pom.xml‎

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Original file line numberDiff line numberDiff line change
@@ -60,11 +60,6 @@
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<artifactId>protobuf-java</artifactId>
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<version>${protobuf.version}</version>
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</dependency>
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<dependency>
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<groupId>io.seruco.encoding</groupId>
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<artifactId>base62</artifactId>
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<version>0.1.2</version>
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</dependency>
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<!-- Audio -->
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<dependency>

‎core/src/main/java/xyz/gianlu/librespot/mercury/model/AlbumId.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
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package xyz.gianlu.librespot.mercury.model;
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3-
import io.seruco.encoding.base62.Base62;
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import org.jetbrains.annotations.NotNull;
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import xyz.gianlu.librespot.common.Base62;
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import xyz.gianlu.librespot.common.Utils;
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import java.util.regex.Matcher;

‎core/src/main/java/xyz/gianlu/librespot/mercury/model/ArtistId.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
11
package xyz.gianlu.librespot.mercury.model;
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3-
import io.seruco.encoding.base62.Base62;
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import org.jetbrains.annotations.NotNull;
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import xyz.gianlu.librespot.common.Base62;
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import xyz.gianlu.librespot.common.Utils;
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import java.util.regex.Matcher;

‎core/src/main/java/xyz/gianlu/librespot/mercury/model/EpisodeId.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
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package xyz.gianlu.librespot.mercury.model;
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3-
import io.seruco.encoding.base62.Base62;
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import org.jetbrains.annotations.NotNull;
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import xyz.gianlu.librespot.common.Base62;
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import xyz.gianlu.librespot.common.Utils;
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import xyz.gianlu.librespot.common.proto.Spirc;
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‎core/src/main/java/xyz/gianlu/librespot/mercury/model/ShowId.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
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package xyz.gianlu.librespot.mercury.model;
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3-
import io.seruco.encoding.base62.Base62;
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import org.jetbrains.annotations.NotNull;
4+
import xyz.gianlu.librespot.common.Base62;
55
import xyz.gianlu.librespot.common.Utils;
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import java.util.regex.Matcher;

‎core/src/main/java/xyz/gianlu/librespot/mercury/model/TrackId.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
11
package xyz.gianlu.librespot.mercury.model;
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3-
import io.seruco.encoding.base62.Base62;
43
import org.jetbrains.annotations.NotNull;
4+
import xyz.gianlu.librespot.common.Base62;
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import xyz.gianlu.librespot.common.Utils;
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import xyz.gianlu.librespot.common.proto.Spirc;
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‎core/src/main/java/xyz/gianlu/librespot/player/tracks/PlaylistProvider.java‎

Lines changed: 4 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -81,7 +81,7 @@ public void unshuffleTracks() {
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8282
int size = tracks.size() - 1;
8383
int[] exchanges = getShuffleExchanges(size, shuffleSeed);
84-
for (int i = 2; i < size; i++) {
84+
for (int i = 1; i < size; i++) {
8585
int n = exchanges[size - i - 1];
8686
Collections.swap(tracks, i, n + 1);
8787
}
@@ -121,6 +121,9 @@ public void unshuffleTracks() {
121121
}
122122
}
123123

124+
if (rebuildState.isEmpty())
125+
throw new IllegalStateException("State cannot be empty!");
126+
124127
state.clearTrack();
125128
state.addAllTrack(rebuildState);
126129
state.setPlayingTrackIndex(0);

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