StringUtils (H2 Database Engine 2.0.0 API)

java.lang.Object
- org.h2.util.StringUtils

```
public class StringUtils
extends Object
```
A few String utility functions.

方法概要

所有方法静态方法具体方法
限定符和类型	方法和说明
`static String`	`addAsterisk(String s, int index)` Add an asterisk ('[*]') at the given position.
`static StringBuilder`	`appendHex(StringBuilder builder, long x, int bytes)` Appends specified number of trailing bytes from unsigned long value to a specified string builder.
`static StringBuilder`	`appendTwoDigits(StringBuilder builder, int positiveValue)` Append a zero-padded number from 00 to 99 to a string builder.
`static StringBuilder`	`appendZeroPadded(StringBuilder builder, int length, long positiveValue)` Append a zero-padded number to a string builder.
`static String`	`arrayCombine(String[] list, char separatorChar)` Combine an array of strings to one array using the given separator character.
`static String[]`	`arraySplit(String s, char separatorChar, boolean trim)` Split a string into an array of strings using the given separator.
`static String`	`cache(String s)` Get the string from the cache if possible.
`static void`	`clearCache()` Clear the cache.
`static char[]`	`cloneCharArray(char[] chars)` Create a new char array and copy all the data.
`static String`	`convertBytesToHex(byte[] value)` Convert a byte array to a hex encoded string.
`static String`	`convertBytesToHex(byte[] value, int len)` Convert a byte array to a hex encoded string.
`static StringBuilder`	`convertBytesToHex(StringBuilder builder, byte[] value)` Convert a byte array to a hex encoded string and appends it to a specified string builder.
`static StringBuilder`	`convertBytesToHex(StringBuilder builder, byte[] value, int len)` Convert a byte array to a hex encoded string and appends it to a specified string builder.
`static byte[]`	`convertHexToBytes(String s)` Convert a hex encoded string to a byte array.
`static ByteArrayOutputStream`	`convertHexWithSpacesToBytes(ByteArrayOutputStream baos, String s, int start, int end)` Parses a hex encoded string with possible space separators and appends the decoded binary string to the specified output stream.
`static String`	`decodeUnicodeStringSQL(String s, int uencode)` Decodes a Unicode SQL string.
`static String`	`escapeMetaDataPattern(String pattern)` Escape table or schema patterns used for DatabaseMetaData functions.
`static StringBuilder`	`indent(StringBuilder builder, String s, int spaces, boolean newline)` Indents a string with spaces and appends it to a specified builder.
`static boolean`	`isNullOrEmpty(String s)` Check if a String is null or empty (the length is null).
`static boolean`	`isNumber(String s)` Check if this string is a decimal number.
`static boolean`	`isWhitespaceOrEmpty(String s)` Check if the specified string is empty or contains only whitespace.
`static String`	`javaDecode(String s)` Decode a text that is encoded as a Java string literal.
`static String`	`javaEncode(String s)` Convert a string to a Java literal using the correct escape sequences.
`static void`	`javaEncode(String s, StringBuilder buff, boolean forSQL)` Convert a string to a Java literal using the correct escape sequences.
`static String`	`pad(String string, int n, String padding, boolean right)` Pad a string.
`static int`	`parseUInt31(String s, int start, int end)` Parses an unsigned 31-bit integer.
`static String`	`quoteIdentifier(String s)` Enclose a string with double quotes.
`static StringBuilder`	`quoteIdentifier(StringBuilder builder, String s)` Enclose a string with double quotes and append it to the specified string builder.
`static String`	`quoteJavaIntArray(int[] array)` Convert an int array to the Java source code that represents this array.
`static String`	`quoteJavaString(String s)` Convert a string to the Java literal and enclose it with double quotes.
`static String`	`quoteJavaStringArray(String[] array)` Convert a string array to the Java source code that represents this array.
`static String`	`quoteStringSQL(String s)` Convert a string to a SQL literal.
`static StringBuilder`	`quoteStringSQL(StringBuilder builder, String s)` Convert a string to a SQL character string literal.
`static String`	`replaceAll(String s, String before, String after)` Replace all occurrences of the before string with the after string.
`static String`	`toLowerEnglish(String s)` Convert a string to lowercase using the English locale.
`static String`	`toUpperEnglish(String s)` Convert a string to uppercase using the English locale.
`static String`	`trim(String s, boolean leading, boolean trailing, String sp)` Trim a character from a string.
`static StringBuilder`	`trimSubstring(StringBuilder builder, String s, int beginIndex, int endIndex)` Trim a whitespace from a substring and append it to a specified string builder.
`static String`	`trimSubstring(String s, int beginIndex)` Trim a whitespace from a substring.
`static String`	`trimSubstring(String s, int beginIndex, int endIndex)` Trim a whitespace from a substring.
`static String`	`truncateString(String s, int maximumLength)` Truncates the specified string to the specified length.
`static String`	`urlDecode(String encoded)` Decode the URL to a string.
`static String`	`urlEncode(String s)` Encode the string as a URL.
`static String`	`xmlAttr(String name, String value)` Creates an XML attribute of the form name="value".
`static String`	`xmlCData(String data)` Converts the data to a CDATA element.
`static String`	`xmlComment(String data)` Escapes a comment.
`static String`	`xmlNode(String name, String attributes, String content)` Create an XML node with optional attributes and content.
`static String`	`xmlNode(String name, String attributes, String content, boolean indent)` Create an XML node with optional attributes and content.
`static String`	`xmlStartDoc()` Returns <?
`static String`	`xmlText(String text)` Escapes an XML text element.
`static String`	`xmlText(String text, boolean escapeNewline)` Escapes an XML text element.

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 方法详细资料
  - toUpperEnglish
```
public static String toUpperEnglish(String s)
```
    Convert a string to uppercase using the English locale.
    
    参数:
    
    s - the test to convert
    
    返回:
    
    the uppercase text
  - toLowerEnglish
```
public static String toLowerEnglish(String s)
```
    Convert a string to lowercase using the English locale.
    
    参数:
    
    s - the text to convert
    
    返回:
    
    the lowercase text
  - quoteStringSQL
```
public static String quoteStringSQL(String s)
```
    Convert a string to a SQL literal. Null is converted to NULL. The text is enclosed in single quotes. If there are any special characters, the method STRINGDECODE is used.
    
    参数:
    
    s - the text to convert.
    
    返回:
    
    the SQL literal
  - quoteStringSQL
```
public static StringBuilder quoteStringSQL(StringBuilder builder,
                                           String s)
```
    Convert a string to a SQL character string literal. Null is converted to NULL. If there are any special characters, the Unicode character string literal is used.
    
    参数:
    
    builder - string builder to append result to
    
    s - the text to convert
    
    返回:
    
    the specified string builder
  - decodeUnicodeStringSQL
```
public static String decodeUnicodeStringSQL(String s,
                                            int uencode)
```
    Decodes a Unicode SQL string.
    
    参数:
    
    s - the string to decode
    
    uencode - the code point of UENCODE character, or '\\'
    
    返回:
    
    the decoded string
    
    抛出:
    
    DbException - on format exception
  - javaEncode
```
public static String javaEncode(String s)
```
    Convert a string to a Java literal using the correct escape sequences. The literal is not enclosed in double quotes. The result can be used in properties files or in Java source code.
    
    参数:
    
    s - the text to convert
    
    返回:
    
    the Java representation
  - javaEncode
```
public static void javaEncode(String s,
                              StringBuilder buff,
                              boolean forSQL)
```
    Convert a string to a Java literal using the correct escape sequences. The literal is not enclosed in double quotes. The result can be used in properties files or in Java source code.
    
    参数:
    
    s - the text to convert
    
    buff - the Java representation to return
    
    forSQL - true if we embedding this inside a STRINGDECODE SQL command
  - addAsterisk
```
public static String addAsterisk(String s,
                                 int index)
```
    Add an asterisk ('[*]') at the given position. This format is used to show where parsing failed in a statement.
    
    参数:
    
    s - the text
    
    index - the position
    
    返回:
    
    the text with asterisk
  - javaDecode
```
public static String javaDecode(String s)
```
    Decode a text that is encoded as a Java string literal. The Java properties file format and Java source code format is supported.
    
    参数:
    
    s - the encoded string
    
    返回:
    
    the string
  - quoteJavaString
```
public static String quoteJavaString(String s)
```
    Convert a string to the Java literal and enclose it with double quotes. Null will result in "null" (without double quotes).
    
    参数:
    
    s - the text to convert
    
    返回:
    
    the Java representation
  - quoteJavaStringArray
```
public static String quoteJavaStringArray(String[] array)
```
    Convert a string array to the Java source code that represents this array. Null will be converted to 'null'.
    
    参数:
    
    array - the string array
    
    返回:
    
    the Java source code (including new String[]{})
  - quoteJavaIntArray
```
public static String quoteJavaIntArray(int[] array)
```
    Convert an int array to the Java source code that represents this array. Null will be converted to 'null'.
    
    参数:
    
    array - the int array
    
    返回:
    
    the Java source code (including new int[]{})
  - urlEncode
```
public static String urlEncode(String s)
```
    Encode the string as a URL.
    
    参数:
    
    s - the string to encode
    
    返回:
    
    the encoded string
  - urlDecode
```
public static String urlDecode(String encoded)
```
    Decode the URL to a string.
    
    参数:
    
    encoded - the encoded URL
    
    返回:
    
    the decoded string
  - arraySplit
```
public static String[] arraySplit(String s,
                                  char separatorChar,
                                  boolean trim)
```
    Split a string into an array of strings using the given separator. A null string will result in a null array, and an empty string in a zero element array.
    
    参数:
    
    s - the string to split
    
    separatorChar - the separator character
    
    trim - whether each element should be trimmed
    
    返回:
    
    the array list
  - arrayCombine
```
public static String arrayCombine(String[] list,
                                  char separatorChar)
```
    Combine an array of strings to one array using the given separator character. A backslash and the separator character and escaped using a backslash.
    
    参数:
    
    list - the string array
    
    separatorChar - the separator character
    
    返回:
    
    the combined string
  - xmlAttr
```
public static String xmlAttr(String name,
                             String value)
```
    Creates an XML attribute of the form name="value". A single space is prepended to the name, so that multiple attributes can be concatenated.
    
    参数:
    
    name - the attribute name
    
    value - the attribute value
    
    返回:
    
    the attribute
  - xmlNode
```
public static String xmlNode(String name,
                             String attributes,
                             String content)
```
    Create an XML node with optional attributes and content. The data is indented with 4 spaces if it contains a newline character.
    
    参数:
    
    name - the element name
    
    attributes - the attributes (may be null)
    
    content - the content (may be null)
    
    返回:
    
    the node
  - xmlNode
```
public static String xmlNode(String name,
                             String attributes,
                             String content,
                             boolean indent)
```
    Create an XML node with optional attributes and content. The data is indented with 4 spaces if it contains a newline character and the indent parameter is set to true.
    
    参数:
    
    name - the element name
    
    attributes - the attributes (may be null)
    
    content - the content (may be null)
    
    indent - whether to indent the content if it contains a newline
    
    返回:
    
    the node
  - indent
```
public static StringBuilder indent(StringBuilder builder,
                                   String s,
                                   int spaces,
                                   boolean newline)
```
    Indents a string with spaces and appends it to a specified builder.
    
    参数:
    
    builder - string builder to append to
    
    s - the string
    
    spaces - the number of spaces
    
    newline - append a newline if there is none
    
    返回:
    
    the specified string builder
  - xmlComment
```
public static String xmlComment(String data)
```
    Escapes a comment. If the data contains '--', it is converted to '- -'. The data is indented with 4 spaces if it contains a newline character.
    
    参数:
    
    data - the comment text
    
    返回:
    
    
  - xmlCData
```
public static String xmlCData(String data)
```
    Converts the data to a CDATA element. If the data contains ']]>', it is escaped as a text element.
    
    参数:
    
    data - the text data
    
    返回:
    
    <![CDATA[data]]>
  - xmlStartDoc
```
public static String xmlStartDoc()
```
    Returns <?xml version="1.0"?>
    
    返回:
    
    <?xml version="1.0"?>
  - xmlText
```
public static String xmlText(String text)
```
    Escapes an XML text element.
    
    参数:
    
    text - the text data
    
    返回:
    
    the escaped text
  - xmlText
```
public static String xmlText(String text,
                             boolean escapeNewline)
```
    Escapes an XML text element.
    
    参数:
    
    text - the text data
    
    escapeNewline - whether to escape newlines
    
    返回:
    
    the escaped text
  - replaceAll
```
public static String replaceAll(String s,
                                String before,
                                String after)
```
    Replace all occurrences of the before string with the after string. Unlike String.replaceAll(String, String) this method reads before and after arguments as plain strings and if before argument is an empty string this method returns original string s.
    
    参数:
    
    s - the string
    
    before - the old text
    
    after - the new text
    
    返回:
    
    the string with the before string replaced
  - quoteIdentifier
```
public static String quoteIdentifier(String s)
```
    Enclose a string with double quotes. A double quote inside the string is escaped using a double quote.
    
    参数:
    
    s - the text
    
    返回:
    
    the double quoted text
  - quoteIdentifier
```
public static StringBuilder quoteIdentifier(StringBuilder builder,
                                            String s)
```
    Enclose a string with double quotes and append it to the specified string builder. A double quote inside the string is escaped using a double quote.
    
    参数:
    
    builder - string builder to append to
    
    s - the text
    
    返回:
    
    the specified builder
  - isNullOrEmpty
```
public static boolean isNullOrEmpty(String s)
```
    Check if a String is null or empty (the length is null).
    
    参数:
    
    s - the string to check
    
    返回:
    
    true if it is null or empty
  - pad
```
public static String pad(String string,
                         int n,
                         String padding,
                         boolean right)
```
    Pad a string. This method is used for the SQL function RPAD and LPAD.
    
    参数:
    
    string - the original string
    
    n - the target length
    
    padding - the padding string
    
    right - true if the padding should be appended at the end
    
    返回:
    
    the padded string
  - cloneCharArray
```
public static char[] cloneCharArray(char[] chars)
```
    Create a new char array and copy all the data. If the size of the byte array is zero, the same array is returned.
    
    参数:
    
    chars - the char array (may be null)
    
    返回:
    
    a new char array
  - trim
```
public static String trim(String s,
                          boolean leading,
                          boolean trailing,
                          String sp)
```
    Trim a character from a string.
    
    参数:
    
    s - the string
    
    leading - if leading characters should be removed
    
    trailing - if trailing characters should be removed
    
    sp - what to remove (only the first character is used) or null for a space
    
    返回:
    
    the trimmed string
  - trimSubstring
```
public static String trimSubstring(String s,
                                   int beginIndex)
```
    Trim a whitespace from a substring. Equivalent of substring(beginIndex).trim().
    
    参数:
    
    s - the string
    
    beginIndex - start index of substring (inclusive)
    
    返回:
    
    trimmed substring
  - trimSubstring
```
public static String trimSubstring(String s,
                                   int beginIndex,
                                   int endIndex)
```
    Trim a whitespace from a substring. Equivalent of substring(beginIndex, endIndex).trim().
    
    参数:
    
    s - the string
    
    beginIndex - start index of substring (inclusive)
    
    endIndex - end index of substring (exclusive)
    
    返回:
    
    trimmed substring
  - trimSubstring
```
public static StringBuilder trimSubstring(StringBuilder builder,
                                          String s,
                                          int beginIndex,
                                          int endIndex)
```
    Trim a whitespace from a substring and append it to a specified string builder. Equivalent of builder.append(substring(beginIndex, endIndex).trim()).
    
    参数:
    
    builder - string builder to append to
    
    s - the string
    
    beginIndex - start index of substring (inclusive)
    
    endIndex - end index of substring (exclusive)
    
    返回:
    
    the specified builder
  - truncateString
```
public static String truncateString(String s,
                                    int maximumLength)
```
    Truncates the specified string to the specified length. This method, unlike String.substring(int, int), doesn't break Unicode code points. If the specified length in characters breaks a valid pair of surrogates, the whole pair is not included into result.
    
    参数:
    
    s - the string to truncate
    
    maximumLength - the maximum length in characters
    
    返回:
    
    the specified string if it isn't longer than the specified maximum length, and the truncated string otherwise
  - cache
```
public static String cache(String s)
```
    Get the string from the cache if possible. If the string has not been found, it is added to the cache. If there is such a string in the cache, that one is returned.
    
    参数:
    
    s - the original string
    
    返回:
    
    a string with the same content, if possible from the cache
  - clearCache
```
public static void clearCache()
```
    Clear the cache. This method is used for testing.
  - parseUInt31
```
public static int parseUInt31(String s,
                              int start,
                              int end)
```
    Parses an unsigned 31-bit integer. Neither - nor + signs are allowed.
    
    参数:
    
    s - string to parse
    
    start - the beginning index, inclusive
    
    end - the ending index, exclusive
    
    返回:
    
    the unsigned int not greater than Integer.MAX_VALUE.
  - convertHexToBytes
```
public static byte[] convertHexToBytes(String s)
```
    Convert a hex encoded string to a byte array.
    
    参数:
    
    s - the hex encoded string
    
    返回:
    
    the byte array
  - convertHexWithSpacesToBytes
```
public static ByteArrayOutputStream convertHexWithSpacesToBytes(ByteArrayOutputStream baos,
                                                                String s,
                                                                int start,
                                                                int end)
```
    Parses a hex encoded string with possible space separators and appends the decoded binary string to the specified output stream.
    
    参数:
    
    baos - the output stream, or null
    
    s - the hex encoded string
    
    start - the start index
    
    end - the end index, exclusive
    
    返回:
    
    the specified output stream or a new output stream
  - convertBytesToHex
```
public static String convertBytesToHex(byte[] value)
```
    Convert a byte array to a hex encoded string.
    
    参数:
    
    value - the byte array
    
    返回:
    
    the hex encoded string
  - convertBytesToHex
```
public static String convertBytesToHex(byte[] value,
                                       int len)
```
    Convert a byte array to a hex encoded string.
    
    参数:
    
    value - the byte array
    
    len - the number of bytes to encode
    
    返回:
    
    the hex encoded string
  - convertBytesToHex
```
public static StringBuilder convertBytesToHex(StringBuilder builder,
                                              byte[] value)
```
    Convert a byte array to a hex encoded string and appends it to a specified string builder.
    
    参数:
    
    builder - string builder to append to
    
    value - the byte array
    
    返回:
    
    the hex encoded string
  - convertBytesToHex
```
public static StringBuilder convertBytesToHex(StringBuilder builder,
                                              byte[] value,
                                              int len)
```
    Convert a byte array to a hex encoded string and appends it to a specified string builder.
    
    参数:
    
    builder - string builder to append to
    
    value - the byte array
    
    len - the number of bytes to encode
    
    返回:
    
    the hex encoded string
  - appendHex
```
public static StringBuilder appendHex(StringBuilder builder,
                                      long x,
                                      int bytes)
```
    Appends specified number of trailing bytes from unsigned long value to a specified string builder.
    
    参数:
    
    builder - string builder to append to
    
    x - value to append
    
    bytes - number of bytes to append
    
    返回:
    
    the specified string builder
  - isNumber
```
public static boolean isNumber(String s)
```
    Check if this string is a decimal number.
    
    参数:
    
    s - the string
    
    返回:
    
    true if it is
  - isWhitespaceOrEmpty
```
public static boolean isWhitespaceOrEmpty(String s)
```
    Check if the specified string is empty or contains only whitespace.
    
    参数:
    
    s - the string
    
    返回:
    
    whether the specified string is empty or contains only whitespace
  - appendTwoDigits
```
public static StringBuilder appendTwoDigits(StringBuilder builder,
                                            int positiveValue)
```
    Append a zero-padded number from 00 to 99 to a string builder.
    
    参数:
    
    builder - the string builder
    
    positiveValue - the number to append
    
    返回:
    
    the specified string builder
  - appendZeroPadded
```
public static StringBuilder appendZeroPadded(StringBuilder builder,
                                             int length,
                                             long positiveValue)
```
    Append a zero-padded number to a string builder.
    
    参数:
    
    builder - the string builder
    
    length - the number of characters to append
    
    positiveValue - the number to append
    
    返回:
    
    the specified string builder
  - escapeMetaDataPattern
```
public static String escapeMetaDataPattern(String pattern)
```
    Escape table or schema patterns used for DatabaseMetaData functions.
    
    参数:
    
    pattern - the pattern
    
    返回:
    
    the escaped pattern

类 StringUtils

方法概要

从类继承的方法 java.lang.Object

方法详细资料

toUpperEnglish

toLowerEnglish

quoteStringSQL

quoteStringSQL

decodeUnicodeStringSQL

javaEncode

javaEncode

addAsterisk

javaDecode

quoteJavaString

quoteJavaStringArray

quoteJavaIntArray

urlEncode

urlDecode

arraySplit

arrayCombine

xmlAttr

xmlNode

xmlNode

indent

xmlComment

xmlCData

xmlStartDoc

xmlText

xmlText

replaceAll

quoteIdentifier

quoteIdentifier

isNullOrEmpty

pad

cloneCharArray

trim

trimSubstring

trimSubstring

trimSubstring

truncateString

cache

clearCache

parseUInt31

convertHexToBytes

convertHexWithSpacesToBytes

convertBytesToHex

convertBytesToHex

convertBytesToHex

convertBytesToHex

appendHex

isNumber

isWhitespaceOrEmpty

appendTwoDigits

appendZeroPadded

escapeMetaDataPattern