stringutils.java

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     * </pre>
     * 
     * @param str  the String to check, may be null
     * @param searchChar  the character to find
     * @return true if the String contains the search character, 
     *  false if not or <code>null</code> string input
     * @since 2.0
     */
    public static boolean contains(String str, char searchChar) {
        if (str == null || str.length() == 0) {
            return false;
        }
        return (str.indexOf(searchChar) >= 0);
    }
    
    /**
     * <p>Find the first index within a String, handling <code>null</code>.
     * This method uses {@link String#indexOf(int)}.</p>
     *
     * <p>A <code>null</code> String will return <code>false</code>.</p>
     * 
     * <pre>
     * StringUtils.contains(null, *)     = false
     * StringUtils.contains(*, null)     = false
     * StringUtils.contains("", "")      = true
     * StringUtils.contains("abc", "")   = true
     * StringUtils.contains("abc", "a")  = true
     * StringUtils.contains("abc", "z")  = false
     * </pre>
     * 
     * @param str  the String to check, may be null
     * @param searchStr  the String to find, may be null
     * @return true if the String contains the search character, 
     *  false if not or <code>null</code> string input
     * @since 2.0
     */
    public static boolean contains(String str, String searchStr) {
        if (str == null || searchStr == null) {
            return false;
        }
        return (str.indexOf(searchStr) >= 0);
    }
    
    // IndexOfAny chars
    //-----------------------------------------------------------------------
    /**
     * <p>Search a String to find the first index of any
     * character in the given set of characters.</p>
     *
     * <p>A <code>null</code> String will return <code>-1</code>.
     * A <code>null</code> or zero length search array will return <code>-1</code>.</p>
     * 
     * <pre>
     * StringUtils.indexOfAny(null, *)                = -1
     * StringUtils.indexOfAny("", *)                  = -1
     * StringUtils.indexOfAny(*, null)                = -1
     * StringUtils.indexOfAny(*, [])                  = -1
     * StringUtils.indexOfAny("zzabyycdxx",['z','a']) = 0
     * StringUtils.indexOfAny("zzabyycdxx",['b','y']) = 3
     * StringUtils.indexOfAny("aba", ['z'])           = -1
     * </pre>
     * 
     * @param str  the String to check, may be null
     * @param searchChars  the chars to search for, may be null
     * @return the index of any of the chars, -1 if no match or null input
     * @since 2.0
     */
     public static int indexOfAny(String str, char[] searchChars) {
         if (str == null || str.length() == 0 || searchChars == null || searchChars.length == 0) {
             return -1;
         }
         for (int i = 0; i < str.length(); i ++) {
             char ch = str.charAt(i);
             for (int j = 0; j < searchChars.length; j++) {
                 if (searchChars[j] == ch) {
                     return i;
                 }
             }
         }
         return -1;
     }

    /**
     * <p>Search a String to find the first index of any
     * character in the given set of characters.</p>
     *
     * <p>A <code>null</code> String will return <code>-1</code>.
     * A <code>null</code> search string will return <code>-1</code>.</p>
     * 
     * <pre>
     * StringUtils.indexOfAny(null, *)            = -1
     * StringUtils.indexOfAny("", *)              = -1
     * StringUtils.indexOfAny(*, null)            = -1
     * StringUtils.indexOfAny(*, "")              = -1
     * StringUtils.indexOfAny("zzabyycdxx", "za") = 0
     * StringUtils.indexOfAny("zzabyycdxx", "by") = 3
     * StringUtils.indexOfAny("aba","z")          = -1
     * </pre>
     *  
     * @param str  the String to check, may be null
     * @param searchChars  the chars to search for, may be null
     * @return the index of any of the chars, -1 if no match or null input
     * @since 2.0
     */
    public static int indexOfAny(String str, String searchChars) {
        if (str == null || str.length() == 0 || searchChars == null || searchChars.length() == 0) {
            return -1;
        }
        return indexOfAny(str, searchChars.toCharArray());
    }

    // IndexOfAnyBut chars
    //-----------------------------------------------------------------------
    /**
     * <p>Search a String to find the first index of any
     * character not in the given set of characters.</p>
     *
     * <p>A <code>null</code> String will return <code>-1</code>.
     * A <code>null</code> or zero length search array will return <code>-1</code>.</p>
     * 
     * <pre>
     * StringUtils.indexOfAnyBut(null, *)           = -1
     * StringUtils.indexOfAnyBut("", *)             = -1
     * StringUtils.indexOfAnyBut(*, null)           = -1
     * StringUtils.indexOfAnyBut(*, [])             = -1
     * StringUtils.indexOfAnyBut("zzabyycdxx",'za') = 3
     * StringUtils.indexOfAnyBut("zzabyycdxx", '')  = 0
     * StringUtils.indexOfAnyBut("aba", 'ab')       = -1
     * </pre>
     * 
     * @param str  the String to check, may be null
     * @param searchChars  the chars to search for, may be null
     * @return the index of any of the chars, -1 if no match or null input
     * @since 2.0
     */
     public static int indexOfAnyBut(String str, char[] searchChars) {
         if (str == null || str.length() == 0 || searchChars == null || searchChars.length == 0) {
             return -1;
         }
         outer: for (int i = 0; i < str.length(); i ++) {
             char ch = str.charAt(i);
             for (int j = 0; j < searchChars.length; j++) {
                 if (searchChars[j] == ch) {
                     continue outer;
                 }
             }
             return i;
         }
         return -1;
     }

    /**
     * <p>Search a String to find the first index of any
     * character not in the given set of characters.</p>
     *
     * <p>A <code>null</code> String will return <code>-1</code>.
     * A <code>null</code> search string will return <code>-1</code>.</p>
     * 
     * <pre>
     * StringUtils.indexOfAnyBut(null, *)            = -1
     * StringUtils.indexOfAnyBut("", *)              = -1
     * StringUtils.indexOfAnyBut(*, null)            = -1
     * StringUtils.indexOfAnyBut(*, "")              = -1
     * StringUtils.indexOfAnyBut("zzabyycdxx", "za") = 3
     * StringUtils.indexOfAnyBut("zzabyycdxx", "")   = 0
     * StringUtils.indexOfAnyBut("aba","ab")         = -1
     * </pre>
     *  
     * @param str  the String to check, may be null
     * @param searchChars  the chars to search for, may be null
     * @return the index of any of the chars, -1 if no match or null input
     * @since 2.0
     */
    public static int indexOfAnyBut(String str, String searchChars) {
        if (str == null || str.length() == 0 || searchChars == null || searchChars.length() == 0) {
            return -1;
        }
        for (int i = 0; i < str.length(); i++) {
            if (searchChars.indexOf(str.charAt(i)) < 0) {
                return i;
            }
        }
        return -1;
    }

    // ContainsOnly
    //-----------------------------------------------------------------------
    /**
     * <p>Checks if the String contains only certain characters.</p>
     *
     * <p>A <code>null</code> String will return <code>false</code>.
     * A <code>null</code> valid character array will return <code>false</code>.
     * An empty String ("") always returns <code>true</code>.</p>
     *
     * <pre>
     * StringUtils.containsOnly(null, *)       = false
     * StringUtils.containsOnly(*, null)       = false
     * StringUtils.containsOnly("", *)         = true
     * StringUtils.containsOnly("ab", '')      = false
     * StringUtils.containsOnly("abab", 'abc') = true
     * StringUtils.containsOnly("ab1", 'abc')  = false
     * StringUtils.containsOnly("abz", 'abc')  = false
     * </pre>
     * 
     * @param str  the String to check, may be null
     * @param valid  an array of valid chars, may be null
     * @return true if it only contains valid chars and is non-null
     */
    public static boolean containsOnly(String str, char[] valid) {
        // All these pre-checks are to maintain API with an older version
        if ( (valid == null) || (str == null) ) {
            return false;
        }
        if (str.length() == 0) {
            return true;
        }
        if (valid.length == 0) {
            return false;
        }
        return indexOfAnyBut(str, valid) == -1;
    }

    /**
     * <p>Checks if the String contains only certain characters.</p>
     *
     * <p>A <code>null</code> String will return <code>false</code>.
     * A <code>null</code> valid character String will return <code>false</code>.
     * An empty String ("") always returns <code>true</code>.</p>
     *
     * <pre>
     * StringUtils.containsOnly(null, *)       = false
     * StringUtils.containsOnly(*, null)       = false
     * StringUtils.containsOnly("", *)         = true
     * StringUtils.containsOnly("ab", "")      = false
     * StringUtils.containsOnly("abab", "abc") = true
     * StringUtils.containsOnly("ab1", "abc")  = false
     * StringUtils.containsOnly("abz", "abc")  = false
     * </pre>
     * 
     * @param str  the String to check, may be null
     * @param validChars  a String of valid chars, may be null
     * @return true if it only contains valid chars and is non-null
     * @since 2.0
     */
    public static boolean containsOnly(String str, String validChars) {
        if (str == null || validChars == null) {
            return false;
        }
        return containsOnly(str, validChars.toCharArray());
    }
    
    // ContainsNone
    //-----------------------------------------------------------------------
    /**
     * <p>Checks that the String does not contain certain characters.</p>
     *
     * <p>A <code>null</code> String will return <code>true</code>.
     * A <code>null</code> invalid character array will return <code>true</code>.
     * An empty String ("") always returns true.</p>
     *
     * <pre>
     * StringUtils.containsNone(null, *)       = true
     * StringUtils.containsNone(*, null)       = true
     * StringUtils.containsNone("", *)         = true
     * StringUtils.containsNone("ab", '')      = true
     * StringUtils.containsNone("abab", 'xyz') = true
     * StringUtils.containsNone("ab1", 'xyz')  = true
     * StringUtils.containsNone("abz", 'xyz')  = false
     * </pre>
     * 
     * @param str  the String to check, may be null
     * @param invalidChars  an array of invalid chars, may be null
     * @return true if it contains none of the invalid chars, or is null
     * @since 2.0
     */
    public static boolean containsNone(String str, char[] invalidChars) {
        if (str == null || invalidChars == null) {
            return true;
        }
        int strSize = str.length();
        int validSize = invalidChars.length;
        for (int i = 0; i < strSize; i++) {
            char ch = str.charAt(i);
            for (int j = 0; j < validSize; j++) {
                if (invalidChars[j] == ch) {
                    return false;
                }
            }
        }
        return true;
    }

    /**
     * <p>Checks that the String does not contain certain characters.</p>
     *
     * <p>A <code>null</code> String will return <code>true</code>.
     * A <code>null</code> invalid character array will return <code>true</code>.
     * An empty String ("") always returns true.</p>
     *
     * <pre>
     * StringUtils.containsNone(null, *)       = true
     * StringUtils.containsNone(*, null)       = true
     * StringUtils.containsNone("", *)         = true
     * StringUtils.containsNone("ab", "")      = true
     * StringUtils.containsNone("abab", "xyz") = true
     * StringUtils.containsNone("ab1", "xyz")  = true
     * StringUtils.containsNone("abz", "xyz")  = false
     * </pre>
     * 
     * @param str  the String to check, may be null
     * @param invalidChars  a String of invalid chars, may be null
     * @return true if it contains none of the invalid chars, or is null
     * @since 2.0
     */
    public static boolean containsNone(String str, String invalidChars) {
        if (str == null || invalidChars == null) {
            return true;
        }
        return containsNone(str, invalidChars.toCharArray());
    }
    
    // IndexOfAny strings
    //-----------------------------------------------------------------------
    /**
     * <p>Find the first index of any of a set of potential substrings.</p>
     *
     * <p>A <code>null</code> String will return <code>-1</code>.
     * A <code>null</code> or zero length search array will return <code>-1</code>.
     * A <code>null</code> search array entry will be ignored, but a search
     * array containing "" will return <code>0</code> if <code>str</code> is not
     * null. This method uses {@link String#indexOf(String)}.</p>