SQLInput

```
public interface SQLInput
```
An input stream that contains a stream of values representing an instance of an SQL structured type or an SQL distinct type. This interface, used only for custom mapping, is used by the driver behind the scenes, and a programmer never directly invokes SQLInput methods. The reader methods (readLong, readBytes, and so on) provide a way for an implementation of the SQLData interface to read the values in an SQLInput object. And as described in SQLData, calls to reader methods must be made in the order that their corresponding attributes appear in the SQL definition of the type. The method wasNull is used to determine whether the last value read was SQL NULL.
When the method getObject is called with an object of a class implementing the interface SQLData, the JDBC driver calls the method SQLData.getSQLType to determine the SQL type of the user-defined type (UDT) being custom mapped. The driver creates an instance of SQLInput, populating it with the attributes of the UDT. The driver then passes the input stream to the method SQLData.readSQL, which in turn calls the SQLInput reader methods in its implementation for reading the attributes from the input stream.

从以下版本开始:

1.2

方法概要

所有方法实例方法抽象方法
限定符和类型	方法	说明
`Array`	`readArray()`	Reads an SQL `ARRAY` value from the stream and returns it as an `Array` object in the Java programming language.
`InputStream`	`readAsciiStream()`	Reads the next attribute in the stream and returns it as a stream of ASCII characters.
`BigDecimal`	`readBigDecimal()`	Reads the next attribute in the stream and returns it as a `java.math.BigDecimal` object in the Java programming language.
`InputStream`	`readBinaryStream()`	Reads the next attribute in the stream and returns it as a stream of uninterpreted bytes.
`Blob`	`readBlob()`	Reads an SQL `BLOB` value from the stream and returns it as a `Blob` object in the Java programming language.
`boolean`	`readBoolean()`	Reads the next attribute in the stream and returns it as a `boolean` in the Java programming language.
`byte`	`readByte()`	Reads the next attribute in the stream and returns it as a `byte` in the Java programming language.
`byte[]`	`readBytes()`	Reads the next attribute in the stream and returns it as an array of bytes in the Java programming language.
`Reader`	`readCharacterStream()`	Reads the next attribute in the stream and returns it as a stream of Unicode characters.
`Clob`	`readClob()`	Reads an SQL `CLOB` value from the stream and returns it as a `Clob` object in the Java programming language.
`Date`	`readDate()`	Reads the next attribute in the stream and returns it as a `java.sql.Date` object.
`double`	`readDouble()`	Reads the next attribute in the stream and returns it as a `double` in the Java programming language.
`float`	`readFloat()`	Reads the next attribute in the stream and returns it as a `float` in the Java programming language.
`int`	`readInt()`	Reads the next attribute in the stream and returns it as an `int` in the Java programming language.
`long`	`readLong()`	Reads the next attribute in the stream and returns it as a `long` in the Java programming language.
`NClob`	`readNClob()`	Reads an SQL `NCLOB` value from the stream and returns it as a `NClob` object in the Java programming language.
`String`	`readNString()`	Reads the next attribute in the stream and returns it as a `String` in the Java programming language.
`Object`	`readObject()`	Reads the datum at the head of the stream and returns it as an `Object` in the Java programming language.
`Ref`	`readRef()`	Reads an SQL `REF` value from the stream and returns it as a `Ref` object in the Java programming language.
`RowId`	`readRowId()`	Reads an SQL `ROWID` value from the stream and returns it as a `RowId` object in the Java programming language.
`short`	`readShort()`	Reads the next attribute in the stream and returns it as a `short` in the Java programming language.
`SQLXML`	`readSQLXML()`	Reads an SQL `XML` value from the stream and returns it as a `SQLXML` object in the Java programming language.
`String`	`readString()`	Reads the next attribute in the stream and returns it as a `String` in the Java programming language.
`Time`	`readTime()`	Reads the next attribute in the stream and returns it as a `java.sql.Time` object.
`Timestamp`	`readTimestamp()`	Reads the next attribute in the stream and returns it as a `java.sql.Timestamp` object.
`URL`	`readURL()`	Reads an SQL `DATALINK` value from the stream and returns it as a `java.net.URL` object in the Java programming language.
`boolean`	`wasNull()`	Retrieves whether the last value read was SQL `NULL`.

- 方法详细资料
  - readString
```
String readString()
           throws SQLException
```
    Reads the next attribute in the stream and returns it as a String in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readBoolean
```
boolean readBoolean()
             throws SQLException
```
    Reads the next attribute in the stream and returns it as a boolean in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns false
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readByte
```
byte readByte()
       throws SQLException
```
    Reads the next attribute in the stream and returns it as a byte in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns 0
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readShort
```
short readShort()
         throws SQLException
```
    Reads the next attribute in the stream and returns it as a short in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns 0
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readInt
```
int readInt()
     throws SQLException
```
    Reads the next attribute in the stream and returns it as an int in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns 0
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readLong
```
long readLong()
       throws SQLException
```
    Reads the next attribute in the stream and returns it as a long in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns 0
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readFloat
```
float readFloat()
         throws SQLException
```
    Reads the next attribute in the stream and returns it as a float in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns 0
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readDouble
```
double readDouble()
           throws SQLException
```
    Reads the next attribute in the stream and returns it as a double in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns 0
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readBigDecimal
```
BigDecimal readBigDecimal()
                   throws SQLException
```
    Reads the next attribute in the stream and returns it as a java.math.BigDecimal object in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readBytes
```
byte[] readBytes()
          throws SQLException
```
    Reads the next attribute in the stream and returns it as an array of bytes in the Java programming language.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readDate
```
Date readDate()
       throws SQLException
```
    Reads the next attribute in the stream and returns it as a java.sql.Date object.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readTime
```
Time readTime()
       throws SQLException
```
    Reads the next attribute in the stream and returns it as a java.sql.Time object.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readTimestamp
```
Timestamp readTimestamp()
                 throws SQLException
```
    Reads the next attribute in the stream and returns it as a java.sql.Timestamp object.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readCharacterStream
```
Reader readCharacterStream()
                    throws SQLException
```
    Reads the next attribute in the stream and returns it as a stream of Unicode characters.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readAsciiStream
```
InputStream readAsciiStream()
                     throws SQLException
```
    Reads the next attribute in the stream and returns it as a stream of ASCII characters.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readBinaryStream
```
InputStream readBinaryStream()
                      throws SQLException
```
    Reads the next attribute in the stream and returns it as a stream of uninterpreted bytes.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readObject
```
Object readObject()
           throws SQLException
```
    Reads the datum at the head of the stream and returns it as an Object in the Java programming language. The actual type of the object returned is determined by the default type mapping, and any customizations present in this stream's type map.
    A type map is registered with the stream by the JDBC driver before the stream is passed to the application.
    When the datum at the head of the stream is an SQL NULL, the method returns null. If the datum is an SQL structured or distinct type, it determines the SQL type of the datum at the head of the stream. If the stream's type map has an entry for that SQL type, the driver constructs an object of the appropriate class and calls the method SQLData.readSQL on that object, which reads additional data from the stream, using the protocol described for that method.
    
    返回:
    
    the datum at the head of the stream as an Object in the Java programming language;null if the datum is SQL NULL
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readRef
```
Ref readRef()
     throws SQLException
```
    Reads an SQL REF value from the stream and returns it as a Ref object in the Java programming language.
    
    返回:
    
    a Ref object representing the SQL REF value at the head of the stream; null if the value read is SQL NULL
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readBlob
```
Blob readBlob()
       throws SQLException
```
    Reads an SQL BLOB value from the stream and returns it as a Blob object in the Java programming language.
    
    返回:
    
    a Blob object representing data of the SQL BLOB value at the head of the stream; null if the value read is SQL NULL
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readClob
```
Clob readClob()
       throws SQLException
```
    Reads an SQL CLOB value from the stream and returns it as a Clob object in the Java programming language.
    
    返回:
    
    a Clob object representing data of the SQL CLOB value at the head of the stream; null if the value read is SQL NULL
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readArray
```
Array readArray()
         throws SQLException
```
    Reads an SQL ARRAY value from the stream and returns it as an Array object in the Java programming language.
    
    返回:
    
    an Array object representing data of the SQL ARRAY value at the head of the stream; null if the value read is SQL NULL
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - wasNull
```
boolean wasNull()
         throws SQLException
```
    Retrieves whether the last value read was SQL NULL.
    
    返回:
    
    true if the most recently read SQL value was SQL NULL; false otherwise
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.2
  - readURL
```
URL readURL()
     throws SQLException
```
    Reads an SQL DATALINK value from the stream and returns it as a java.net.URL object in the Java programming language.
    
    返回:
    
    a java.net.URL object.
    
    抛出:
    
    SQLException - if a database access error occurs, or if a URL is malformed
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.4
  - readNClob
```
NClob readNClob()
         throws SQLException
```
    Reads an SQL NCLOB value from the stream and returns it as a NClob object in the Java programming language.
    
    返回:
    
    a NClob object representing data of the SQL NCLOB value at the head of the stream; null if the value read is SQL NULL
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.6
  - readNString
```
String readNString()
            throws SQLException
```
    Reads the next attribute in the stream and returns it as a String in the Java programming language. It is intended for use when accessing NCHAR,NVARCHAR and LONGNVARCHAR columns.
    
    返回:
    
    the attribute; if the value is SQL NULL, returns null
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.6
  - readSQLXML
```
SQLXML readSQLXML()
           throws SQLException
```
    Reads an SQL XML value from the stream and returns it as a SQLXML object in the Java programming language.
    
    返回:
    
    a SQLXML object representing data of the SQL XML value at the head of the stream; null if the value read is SQL NULL
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.6
  - readRowId
```
RowId readRowId()
         throws SQLException
```
    Reads an SQL ROWID value from the stream and returns it as a RowId object in the Java programming language.
    
    返回:
    
    a RowId object representing data of the SQL ROWID value at the head of the stream; null if the value read is SQL NULL
    
    抛出:
    
    SQLException - if a database access error occurs
    
    SQLFeatureNotSupportedException - if the JDBC driver does not support this method
    
    从以下版本开始:
    
    1.6

接口 SQLInput

方法概要

方法详细资料

readString

readBoolean

readByte

readShort

readInt

readLong

readFloat

readDouble

readBigDecimal

readBytes

readDate

readTime

readTimestamp

readCharacterStream

readAsciiStream

readBinaryStream

readObject

readRef

readBlob

readClob

readArray

wasNull

readURL

readNClob

readNString

readSQLXML

readRowId