Csv (H2 Database Engine 2.0.0 API)

java.lang.Object
- org.h2.tools.Csv

所有已实现的接口:

SimpleRowSource
```
public class Csv
extends Object
implements SimpleRowSource
```
A facility to read from and write to CSV (comma separated values) files. When reading, the BOM (the byte-order-mark) character 0xfeff at the beginning of the file is ignored.

作者:

Thomas Mueller, Sylvain Cuaz

构造器概要

构造器
构造器和说明

Csv()

构造器
构造器和说明
`Csv()`

方法概要

所有方法实例方法具体方法
限定符和类型	方法和说明
`void`	`close()` INTERNAL
`boolean`	`getCaseSensitiveColumnNames()` Get the current case sensitive column names setting.
`char`	`getEscapeCharacter()` Get the current escape character.
`char`	`getFieldDelimiter()` Get the current field delimiter.
`char`	`getFieldSeparatorRead()` Get the current field separator for reading.
`String`	`getFieldSeparatorWrite()` Get the current field separator for writing.
`char`	`getLineCommentCharacter()` Get the line comment character.
`String`	`getLineSeparator()` Get the line separator used for writing.
`String`	`getNullString()` Get the current null string.
`boolean`	`getPreserveWhitespace()` Whether whitespace in unquoted text is preserved.
`boolean`	`getWriteColumnHeader()` Whether the column header is written.
`ResultSet`	`read(Reader reader, String[] colNames)` Reads CSV data from a reader and returns a result set.
`ResultSet`	`read(String inputFileName, String[] colNames, String charset)` Reads from the CSV file and returns a result set.
`Object[]`	`readRow()` INTERNAL
`void`	`reset()` INTERNAL
`void`	`setCaseSensitiveColumnNames(boolean caseSensitiveColumnNames)` Override the case sensitive column names setting.
`void`	`setEscapeCharacter(char escapeCharacter)` Set the escape character.
`void`	`setFieldDelimiter(char fieldDelimiter)` Set the field delimiter.
`void`	`setFieldSeparatorRead(char fieldSeparatorRead)` Override the field separator for reading.
`void`	`setFieldSeparatorWrite(String fieldSeparatorWrite)` Override the field separator for writing.
`void`	`setLineCommentCharacter(char lineCommentCharacter)` Set the line comment character.
`void`	`setLineSeparator(String lineSeparator)` Set the line separator used for writing.
`void`	`setNullString(String nullString)` Set the value that represents NULL.
`String`	`setOptions(String options)` INTERNAL.
`void`	`setPreserveWhitespace(boolean value)` Enable or disable preserving whitespace in unquoted text.
`void`	`setWriteColumnHeader(boolean value)` Enable or disable writing the column header.
`int`	`write(Connection conn, String outputFileName, String sql, String charset)` Writes the result set of a query to a file in the CSV format.
`int`	`write(String outputFileName, ResultSet rs, String charset)` Writes the result set to a file in the CSV format.
`int`	`write(Writer writer, ResultSet rs)` Writes the result set to a file in the CSV format.

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

- 构造器详细资料
  - Csv
```
public Csv()
```
- 方法详细资料
  - write
```
public int write(Writer writer,
                 ResultSet rs)
          throws SQLException
```
    Writes the result set to a file in the CSV format.
    
    参数:
    
    writer - the writer
    
    rs - the result set
    
    返回:
    
    the number of rows written
    
    抛出:
    
    SQLException - on failure
  - write
```
public int write(String outputFileName,
                 ResultSet rs,
                 String charset)
          throws SQLException
```
    Writes the result set to a file in the CSV format. The result set is read using the following loop:
```
 while (rs.next()) {
     writeRow(row);
 }
 
```
    参数:
    
    outputFileName - the name of the csv file
    
    rs - the result set - the result set must be positioned before the first row.
    
    charset - the charset or null to use the system default charset
    
    返回:
    
    the number of rows written
    
    抛出:
    
    SQLException - on failure
  - write
```
public int write(Connection conn,
                 String outputFileName,
                 String sql,
                 String charset)
          throws SQLException
```
    Writes the result set of a query to a file in the CSV format.
    
    参数:
    
    conn - the connection
    
    outputFileName - the file name
    
    sql - the query
    
    charset - the charset or null to use the system default charset (see system property file.encoding)
    
    返回:
    
    the number of rows written
    
    抛出:
    
    SQLException - on failure
  - read
```
public ResultSet read(String inputFileName,
                      String[] colNames,
                      String charset)
               throws SQLException
```
    Reads from the CSV file and returns a result set. The rows in the result set are created on demand, that means the file is kept open until all rows are read or the result set is closed. If the columns are read from the CSV file, then the following rules are used: columns names that start with a letter or '_', and only contain letters, '_', and digits, are considered case insensitive and are converted to uppercase. Other column names are considered case sensitive (that means they need to be quoted when accessed).
    
    参数:
    
    inputFileName - the file name
    
    colNames - or null if the column names should be read from the CSV file
    
    charset - the charset or null to use the system default charset
    
    返回:
    
    the result set
    
    抛出:
    
    SQLException - on failure
  - read
```
public ResultSet read(Reader reader,
                      String[] colNames)
               throws IOException
```
    Reads CSV data from a reader and returns a result set. The rows in the result set are created on demand, that means the reader is kept open until all rows are read or the result set is closed.
    
    参数:
    
    reader - the reader
    
    colNames - or null if the column names should be read from the CSV file
    
    返回:
    
    the result set
    
    抛出:
    
    IOException - on failure
  - readRow
```
public Object[] readRow()
                 throws SQLException
```
    INTERNAL
    
    指定者:
    
    readRow 在接口中 SimpleRowSource
    
    返回:
    
    the row or null
    
    抛出:
    
    SQLException - on failure
  - close
```
public void close()
```
    INTERNAL
    
    指定者:
    
    close 在接口中 SimpleRowSource
  - reset
```
public void reset()
           throws SQLException
```
    INTERNAL
    
    指定者:
    
    reset 在接口中 SimpleRowSource
    
    抛出:
    
    SQLException - if this operation is not supported
  - setFieldSeparatorWrite
```
public void setFieldSeparatorWrite(String fieldSeparatorWrite)
```
    Override the field separator for writing. The default is ",".
    
    参数:
    
    fieldSeparatorWrite - the field separator
  - getFieldSeparatorWrite
```
public String getFieldSeparatorWrite()
```
    Get the current field separator for writing.
    
    返回:
    
    the field separator
  - setCaseSensitiveColumnNames
```
public void setCaseSensitiveColumnNames(boolean caseSensitiveColumnNames)
```
    Override the case sensitive column names setting. The default is false. If enabled, the case of all column names is always preserved.
    
    参数:
    
    caseSensitiveColumnNames - whether column names are case sensitive
  - getCaseSensitiveColumnNames
```
public boolean getCaseSensitiveColumnNames()
```
    Get the current case sensitive column names setting.
    
    返回:
    
    whether column names are case sensitive
  - setFieldSeparatorRead
```
public void setFieldSeparatorRead(char fieldSeparatorRead)
```
    Override the field separator for reading. The default is ','.
    
    参数:
    
    fieldSeparatorRead - the field separator
  - getFieldSeparatorRead
```
public char getFieldSeparatorRead()
```
    Get the current field separator for reading.
    
    返回:
    
    the field separator
  - setLineCommentCharacter
```
public void setLineCommentCharacter(char lineCommentCharacter)
```
    Set the line comment character. The default is character code 0 (line comments are disabled).
    
    参数:
    
    lineCommentCharacter - the line comment character
  - getLineCommentCharacter
```
public char getLineCommentCharacter()
```
    Get the line comment character.
    
    返回:
    
    the line comment character, or 0 if disabled
  - setFieldDelimiter
```
public void setFieldDelimiter(char fieldDelimiter)
```
    Set the field delimiter. The default is " (a double quote). The value 0 means no field delimiter is used.
    
    参数:
    
    fieldDelimiter - the field delimiter
  - getFieldDelimiter
```
public char getFieldDelimiter()
```
    Get the current field delimiter.
    
    返回:
    
    the field delimiter
  - setEscapeCharacter
```
public void setEscapeCharacter(char escapeCharacter)
```
    Set the escape character. The escape character is used to escape the field delimiter. This is needed if the data contains the field delimiter. The default escape character is " (a double quote), which is the same as the field delimiter. If the field delimiter and the escape character are both " (double quote), and the data contains a double quote, then an additional double quote is added. Example:
```
 Data: He said "Hello".
 Escape character: "
 Field delimiter: "
 CSV file: "He said ""Hello""."
 
```
    If the field delimiter is a double quote and the escape character is a backslash, then escaping is done similar to Java (however, only the field delimiter is escaped). Example:
```
 Data: He said "Hello".
 Escape character: \
 Field delimiter: "
 CSV file: "He said \"Hello\"."
 
```
    The value 0 means no escape character is used.
    参数:
    
    escapeCharacter - the escape character
  - getEscapeCharacter
```
public char getEscapeCharacter()
```
    Get the current escape character.
    
    返回:
    
    the escape character
  - setLineSeparator
```
public void setLineSeparator(String lineSeparator)
```
    Set the line separator used for writing. This is usually a line feed (\n or \r\n depending on the system settings). The line separator is written after each row (including the last row), so this option can include an end-of-row marker if needed.
    
    参数:
    
    lineSeparator - the line separator
  - getLineSeparator
```
public String getLineSeparator()
```
    Get the line separator used for writing.
    
    返回:
    
    the line separator
  - setNullString
```
public void setNullString(String nullString)
```
    Set the value that represents NULL. It is only used for non-delimited values.
    
    参数:
    
    nullString - the null
  - getNullString
```
public String getNullString()
```
    Get the current null string.
    
    返回:
    
    the null string.
  - setPreserveWhitespace
```
public void setPreserveWhitespace(boolean value)
```
    Enable or disable preserving whitespace in unquoted text.
    
    参数:
    
    value - the new value for the setting
  - getPreserveWhitespace
```
public boolean getPreserveWhitespace()
```
    Whether whitespace in unquoted text is preserved.
    
    返回:
    
    the current value for the setting
  - setWriteColumnHeader
```
public void setWriteColumnHeader(boolean value)
```
    Enable or disable writing the column header.
    
    参数:
    
    value - the new value for the setting
  - getWriteColumnHeader
```
public boolean getWriteColumnHeader()
```
    Whether the column header is written.
    
    返回:
    
    the current value for the setting
  - setOptions
```
public String setOptions(String options)
```
    INTERNAL. Parse and set the CSV options.
    
    参数:
    
    options - the options
    
    返回:
    
    the character set

类 Csv

构造器概要

方法概要

从类继承的方法 java.lang.Object

构造器详细资料

Csv

方法详细资料

write

write

write

read

read

readRow

close

reset

setFieldSeparatorWrite

getFieldSeparatorWrite

setCaseSensitiveColumnNames

getCaseSensitiveColumnNames

setFieldSeparatorRead

getFieldSeparatorRead

setLineCommentCharacter

getLineCommentCharacter

setFieldDelimiter

getFieldDelimiter

setEscapeCharacter

getEscapeCharacter

setLineSeparator

getLineSeparator

setNullString

getNullString

setPreserveWhitespace

getPreserveWhitespace

setWriteColumnHeader

getWriteColumnHeader

setOptions