added classes for Base32 and Base62 encoding and decoding

This commit is contained in:
Sebastian Sdorra
2012-09-05 16:05:07 +02:00
parent a94a2bf774
commit e8d92f485c
6 changed files with 502 additions and 0 deletions

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/**
* Copyright (c) 2010, Sebastian Sdorra All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer. 2. Redistributions in
* binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution. 3. Neither the name of SCM-Manager;
* nor the names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* http://bitbucket.org/sdorra/scm-manager
*
*/
package sonia.scm.util;
//~--- non-JDK imports --------------------------------------------------------
import com.google.common.base.Preconditions;
import com.google.common.base.Strings;
//~--- JDK imports ------------------------------------------------------------
import java.math.BigInteger;
/**
* Abstract base class for encoding and decoding BaseX.
*
* @author Sebastian Sdorra
* @since 1.21
*/
public abstract class AbstractBase
{
/**
* Decode a BaseX string to a BigInteger value.
*
*
* @param chars char table
* @param base base value
* @param value BaseX string to decode
*
* @return decoded value
*/
protected static BigInteger decode(String chars, BigInteger base,
String value)
{
Preconditions.checkArgument(!Strings.isNullOrEmpty(value),
"string must not be empty");
BigInteger result = BigInteger.ZERO;
int digits = value.length();
for (int index = 0; index < digits; index++)
{
int digit = chars.indexOf(value.charAt(digits - index - 1));
result = result.add(BigInteger.valueOf(digit).multiply(base.pow(index)));
}
return result;
}
/**
* Encode BigInteger value to a BaseX string.
*
*
* @param chars char table
* @param base base value
* @param value BigInteger value to encode
*
* @return encoded BaseX string
*/
protected static String encode(String chars, BigInteger base,
BigInteger value)
{
Preconditions.checkArgument(value.compareTo(BigInteger.ZERO) >= 0,
"value must be positive");
StringBuilder buffer = new StringBuilder();
while (value.compareTo(BigInteger.ZERO) == 1)
{
BigInteger[] divmod = value.divideAndRemainder(base);
value = divmod[0];
int digit = divmod[1].intValue();
buffer.insert(0, chars.charAt(digit));
}
String result = buffer.toString();
if (result.length() == 0)
{
result = chars.substring(0, 1);
}
return result;
}
}

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/**
* Copyright (c) 2010, Sebastian Sdorra All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer. 2. Redistributions in
* binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution. 3. Neither the name of SCM-Manager;
* nor the names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* http://bitbucket.org/sdorra/scm-manager
*
*/
package sonia.scm.util;
//~--- JDK imports ------------------------------------------------------------
import java.math.BigInteger;
/**
* Provides Base32 encoding and decoding for long values.
*
* @author Sebastian Sdorra
* @since 1.21
*/
public final class Base32 extends AbstractBase
{
/** base value */
private static final BigInteger BASE = BigInteger.valueOf(32l);
/** char table */
private static final String CHARS = "0123456789bcdefghjkmnpqrstuvwxyz";
//~--- methods --------------------------------------------------------------
/**
* Decode a Base32 string to a long value.
*
*
* @param value Base32 string value
*
* @return decoded long value
*/
public static long decode(String value)
{
return decode(CHARS, BASE, value).longValue();
}
/**
* Encode long value to a Base32 string.
*
*
* @param value long value to encode
*
* @return encoded Base32 string
*/
public static String encode(long value)
{
return encode(CHARS, BASE, BigInteger.valueOf(value));
}
}

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/**
* Copyright (c) 2010, Sebastian Sdorra All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer. 2. Redistributions in
* binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution. 3. Neither the name of SCM-Manager;
* nor the names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* http://bitbucket.org/sdorra/scm-manager
*
*/
package sonia.scm.util;
//~--- JDK imports ------------------------------------------------------------
import java.math.BigInteger;
/**
* Provides Base62 encoding and decoding for long values.
*
* @author Sebastian Sdorra
* @since 1.21
*/
public final class Base62 extends AbstractBase
{
/** base value */
private static final BigInteger BASE = BigInteger.valueOf(62l);
/** char table */
private static final String CHARS =
"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
//~--- methods --------------------------------------------------------------
/**
* Decode a Base62 string to a long value.
*
*
* @param value Base62 string value
*
* @return decoded long value
*/
public static long decode(String value)
{
return decode(CHARS, BASE, value).longValue();
}
/**
* Encode long value to a Base62 string.
*
*
* @param value long value to encode
*
* @return encoded Base62 string
*/
public static String encode(long value)
{
return encode(CHARS, BASE, BigInteger.valueOf(value));
}
}

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/**
* Copyright (c) 2010, Sebastian Sdorra All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer. 2. Redistributions in
* binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution. 3. Neither the name of SCM-Manager;
* nor the names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* http://bitbucket.org/sdorra/scm-manager
*
*/
package sonia.scm.util;
/**
*
* @author Sebastian Sdorra
*/
public class Base32Test extends BaseXTestBase
{
/**
* Method description
*
*
* @param value
*
* @return
*/
@Override
protected long decode(String value)
{
return Base32.decode(value);
}
/**
* Method description
*
*
* @param value
*
* @return
*/
@Override
protected String encode(long value)
{
return Base32.encode(value);
}
}

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/**
* Copyright (c) 2010, Sebastian Sdorra All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer. 2. Redistributions in
* binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution. 3. Neither the name of SCM-Manager;
* nor the names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* http://bitbucket.org/sdorra/scm-manager
*
*/
package sonia.scm.util;
/**
*
* @author Sebastian Sdorra
*/
public class Base62Test extends BaseXTestBase
{
/**
* Method description
*
*
* @param value
*
* @return
*/
@Override
protected long decode(String value)
{
return Base62.decode(value);
}
/**
* Method description
*
*
* @param value
*
* @return
*/
@Override
protected String encode(long value)
{
return Base62.encode(value);
}
}

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/**
* Copyright (c) 2010, Sebastian Sdorra All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer. 2. Redistributions in
* binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution. 3. Neither the name of SCM-Manager;
* nor the names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* http://bitbucket.org/sdorra/scm-manager
*
*/
package sonia.scm.util;
//~--- non-JDK imports --------------------------------------------------------
import org.junit.Test;
import static org.hamcrest.Matchers.*;
import static org.junit.Assert.*;
/**
*
* @author Sebastian Sdorra
*/
public abstract class BaseXTestBase
{
/**
* Method description
*
*
* @param value
*
* @return
*/
protected abstract long decode(String value);
/**
* Method description
*
*
* @param value
*
* @return
*/
protected abstract String encode(long value);
/**
* Method description
*
*/
@Test
public void testEncodeAndDecode()
{
long value = 1234;
String valueString = String.valueOf(value);
String enc = encode(value);
assertThat(enc, not(equalTo(valueString)));
assertEquals(value, decode(enc));
}
}