Java String Shorten shortenDbName(String dbName, int desiredLength)

Description

Start by removing all vowels, then pull 1 letter at a time off the end of each _ separated segment, go until it is less than or equal to the desired length

License

Apache License

Parameter

Parameter	Description
dbName	a parameter
desiredLength	a parameter

Return

shortened String

Declaration

public static String shortenDbName(String dbName, int desiredLength) 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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./*from   www  . j av  a  2  s. co m*/
 *******************************************************************************/

public class Main {
    public static String vowelBag = "aeiouyAEIOUY";

    /**  Start by removing all vowels, then pull 1 letter at a time off the end of each _ separated segment, go until it is less than or equal to the desired length
     *
     * @param dbName
     * @param desiredLength
     * @return shortened String
     */
    public static String shortenDbName(String dbName, int desiredLength) {
        StringBuilder dbBuf = new StringBuilder(dbName);
        if (dbBuf.length() > desiredLength) {
            // remove one vowel at a time, starting at beginning
            for (int i = dbBuf.length() - 1; i > 0; i--) {
                // don't remove vowels that are at the beginning of the string (taken care of by the i > 0) or right after an underscore
                if (dbBuf.charAt(i - 1) == '_') {
                    continue;
                }

                char curChar = dbBuf.charAt(i);
                if (vowelBag.indexOf(curChar) > 0) {
                    dbBuf.deleteCharAt(i);
                }
            }
        }

        // remove all double underscores
        while (dbBuf.indexOf("__") > 0) {
            dbBuf.deleteCharAt(dbBuf.indexOf("__"));
        }

        while (dbBuf.length() > desiredLength) {
            boolean removedChars = false;

            int usIndex = dbBuf.lastIndexOf("_");
            while (usIndex > 0 && dbBuf.length() > desiredLength) {
                // if this is the first word in the group, don't pull letters off unless it is 4 letters or more
                int prevUsIndex = dbBuf.lastIndexOf("_", usIndex - 1);
                if (prevUsIndex < 0 && usIndex < 4) {
                    break;
                }

                // don't remove characters to reduce the size two less than three characters between underscores
                if (prevUsIndex >= 0 && (usIndex - prevUsIndex) <= 4) {
                    usIndex = prevUsIndex;
                    continue;
                }

                // delete the second to last character instead of the last, better chance of being unique
                dbBuf.deleteCharAt(usIndex - 2);
                removedChars = true;
                if (usIndex > 2) {
                    usIndex = dbBuf.lastIndexOf("_", usIndex - 2);
                } else {
                    break;
                }
            }

            // now delete the char at the end of the string if necessary
            if (dbBuf.length() > desiredLength) {
                int removeIndex = dbBuf.length() - 1;
                int prevRemoveIndex = dbBuf.lastIndexOf("_", removeIndex - 1);
                // don't remove characters to reduce the size two less than two characters between underscores
                if (prevRemoveIndex < 0 || (removeIndex - prevRemoveIndex) >= 3) {
                    // delete the second to last character instead of the last, better chance of being unique
                    dbBuf.deleteCharAt(removeIndex - 1);
                    removedChars = true;
                }
            }

            // remove all double underscores
            while (dbBuf.indexOf("__") > 0) {
                dbBuf.deleteCharAt(dbBuf.indexOf("__"));
                removedChars = true;
            }

            // if we didn't remove anything break out to avoid an infinite loop
            if (!removedChars) {
                break;
            }
        }

        // remove all double underscores
        while (dbBuf.indexOf("__") > 0) {
            dbBuf.deleteCharAt(dbBuf.indexOf("__"));
        }

        while (dbBuf.length() > desiredLength) {
            // still not short enough, get more aggressive
            // don't remove the first segment, just remove the second over and over until we are short enough
            int firstUs = dbBuf.indexOf("_");
            if (firstUs > 0) {
                int nextUs = dbBuf.indexOf("_", firstUs + 1);
                if (nextUs > 0) {
                    //Debug.logInfo("couldn't shorten enough normally, removing second segment from " + dbBuf, module);
                    dbBuf.delete(firstUs, nextUs);
                }
            }
        }

        //Debug.logInfo("Shortened " + dbName + " to " + dbBuf.toString(), module);
        return dbBuf.toString();
    }
}

Related

1. shortenClassName(String str)
2. shortenComponentLoggerName(String loggerName)
3. shortenContent(String s, int maxLength)
4. shortenCount(final long count)
5. shortenCount(int count)
6. shortenDerivedIdentifier(final String derivdedIdentifier)
7. shortenFileName(String name)
8. shortenFileName(String text, String filename)
9. shortenGeneratedIdentifier(final String name)