JDK8/Java8源码在线阅读
/*
* Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package javax.sql.rowset;
import java.sql.*;
import javax.sql.*;
import java.io.*;
import java.lang.reflect.*;
/**
* Provides implementations for the methods that set and get
* metadata information about a <code>RowSet</code> object's columns.
* A <code>RowSetMetaDataImpl</code> object keeps track of the
* number of columns in the rowset and maintains an internal array
* of column attributes for each column.
* <P>
* A <code>RowSet</code> object creates a <code>RowSetMetaDataImpl</code>
* object internally in order to set and retrieve information about
* its columns.
* <P>
* NOTE: All metadata in a <code>RowSetMetaDataImpl</code> object
* should be considered as unavailable until the <code>RowSet</code> object
* that it describes is populated.
* Therefore, any <code>RowSetMetaDataImpl</code> method that retrieves information
* is defined as having unspecified behavior when it is called
* before the <code>RowSet</code> object contains data.
*/
public class RowSetMetaDataImpl implements RowSetMetaData, Serializable {
/**
* The number of columns in the <code>RowSet</code> object that created
* this <code>RowSetMetaDataImpl</code> object.
* @serial
*/
private int colCount;
/**
* An array of <code>ColInfo</code> objects used to store information
* about each column in the <code>RowSet</code> object for which
* this <code>RowSetMetaDataImpl</code> object was created. The first
* <code>ColInfo</code> object in this array contains information about
* the first column in the <code>RowSet</code> object, the second element
* contains information about the second column, and so on.
* @serial
*/
private ColInfo[] colInfo;
/**
* Checks to see that the designated column is a valid column number for
* the <code>RowSet</code> object for which this <code>RowSetMetaDataImpl</code>
* was created. To be valid, a column number must be greater than
* <code>0</code> and less than or equal to the number of columns in a row.
* @throws <code>SQLException</code> with the message "Invalid column index"
* if the given column number is out of the range of valid column
* numbers for the <code>RowSet</code> object
*/
private void checkColRange(int col) throws SQLException {
if (col <= 0 || col > colCount) {
throw new SQLException("Invalid column index :"+col);
}
}
/**
* Checks to see that the given SQL type is a valid column type and throws an
* <code>SQLException</code> object if it is not.
* To be valid, a SQL type must be one of the constant values
* in the <code><a href="../../sql/Types.html">java.sql.Types</a></code>
* class.
*
* @param SQLType an <code>int</code> defined in the class <code>java.sql.Types</code>
* @throws SQLException if the given <code>int</code> is not a constant defined in the
* class <code>java.sql.Types</code>
*/
private void checkColType(int SQLType) throws SQLException {
try {
Class<?> c = java.sql.Types.class;
Field[] publicFields = c.getFields();
int fieldValue = 0;
for (int i = 0; i < publicFields.length; i++) {
fieldValue = publicFields[i].getInt(c);
if (fieldValue == SQLType) {
return;
}
}
} catch (Exception e) {
throw new SQLException(e.getMessage());
}
throw new SQLException("Invalid SQL type for column");
}
/**
* Sets to the given number the number of columns in the <code>RowSet</code>
* object for which this <code>RowSetMetaDataImpl</code> object was created.
*
* @param columnCount an <code>int</code> giving the number of columns in the
* <code>RowSet</code> object
* @throws SQLException if the given number is equal to or less than zero
*/
public void setColumnCount(int columnCount) throws SQLException {
if (columnCount <= 0) {
throw new SQLException("Invalid column count. Cannot be less " +
"or equal to zero");
}
colCount = columnCount;
// If the colCount is Integer.MAX_VALUE,
// we do not initialize the colInfo object.
// even if we try to initialize the colCount with
// colCount = Integer.MAx_VALUE-1, the colInfo
// initialization fails throwing an ERROR
// OutOfMemory Exception. So we do not initialize
// colInfo at Integer.MAX_VALUE. This is to pass TCK.
if(!(colCount == Integer.MAX_VALUE)) {
colInfo = new ColInfo[colCount + 1];
for (int i=1; i <= colCount; i++) {
colInfo[i] = new ColInfo();
}
}
}
/**
* Sets whether the designated column is automatically
* numbered, thus read-only, to the given <code>boolean</code>
* value.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns
* in the rowset, inclusive
* @param property <code>true</code> if the given column is
* automatically incremented; <code>false</code>
* otherwise
* @throws SQLException if a database access error occurs or
* the given index is out of bounds
*/
public void setAutoIncrement(int columnIndex, boolean property) throws SQLException {
checkColRange(columnIndex);
colInfo[columnIndex].autoIncrement = property;
}
/**
* Sets whether the name of the designated column is case sensitive to
* the given <code>boolean</code>.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns
* in the rowset, inclusive
* @param property <code>true</code> to indicate that the column
* name is case sensitive; <code>false</code> otherwise
* @throws SQLException if a database access error occurs or
* the given column number is out of bounds
*/
public void setCaseSensitive(int columnIndex, boolean property) throws SQLException {
checkColRange(columnIndex);
colInfo[columnIndex].caseSensitive = property;
}
/**
* Sets whether a value stored in the designated column can be used
* in a <code>WHERE</code> clause to the given <code>boolean</code> value.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number
* of columns in the rowset, inclusive
* @param property <code>true</code> to indicate that a column
* value can be used in a <code>WHERE</code> clause;
* <code>false</code> otherwise
*
* @throws SQLException if a database access error occurs or
* the given column number is out of bounds
*/
public void setSearchable(int columnIndex, boolean property)
throws SQLException {
checkColRange(columnIndex);
colInfo[columnIndex].searchable = property;
}
/**
* Sets whether a value stored in the designated column is a cash
* value to the given <code>boolean</code>.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns,
* inclusive between <code>1</code> and the number of columns, inclusive
* @param property true if the value is a cash value; false otherwise.
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public void setCurrency(int columnIndex, boolean property)
throws SQLException {
checkColRange(columnIndex);
colInfo[columnIndex].currency = property;
}
/**
* Sets whether a value stored in the designated column can be set
* to <code>NULL</code> to the given constant from the interface
* <code>ResultSetMetaData</code>.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param property one of the following <code>ResultSetMetaData</code> constants:
* <code>columnNoNulls</code>,
* <code>columnNullable</code>, or
* <code>columnNullableUnknown</code>
*
* @throws SQLException if a database access error occurs,
* the given column number is out of bounds, or the value supplied
* for the <i>property</i> parameter is not one of the following
* constants:
* <code>ResultSetMetaData.columnNoNulls</code>,
* <code>ResultSetMetaData.columnNullable</code>, or
* <code>ResultSetMetaData.columnNullableUnknown</code>
*/
public void setNullable(int columnIndex, int property) throws SQLException {
if ((property < ResultSetMetaData.columnNoNulls) ||
property > ResultSetMetaData.columnNullableUnknown) {
throw new SQLException("Invalid nullable constant set. Must be " +
"either columnNoNulls, columnNullable or columnNullableUnknown");
}
checkColRange(columnIndex);
colInfo[columnIndex].nullable = property;
}
/**
* Sets whether a value stored in the designated column is a signed
* number to the given <code>boolean</code>.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param property <code>true</code> to indicate that a column
* value is a signed number;
* <code>false</code> to indicate that it is not
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public void setSigned(int columnIndex, boolean property) throws SQLException {
checkColRange(columnIndex);
colInfo[columnIndex].signed = property;
}
/**
* Sets the normal maximum number of chars in the designated column
* to the given number.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param size the maximum size of the column in chars; must be
* <code>0</code> or more
* @throws SQLException if a database access error occurs,
* the given column number is out of bounds, or <i>size</i> is
* less than <code>0</code>
*/
public void setColumnDisplaySize(int columnIndex, int size) throws SQLException {
if (size < 0) {
throw new SQLException("Invalid column display size. Cannot be less " +
"than zero");
}
checkColRange(columnIndex);
colInfo[columnIndex].columnDisplaySize = size;
}
/**
* Sets the suggested column label for use in printouts and
* displays, if any, to <i>label</i>. If <i>label</i> is
* <code>null</code>, the column label is set to an empty string
* ("").
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param label the column label to be used in printouts and displays; if the
* column label is <code>null</code>, an empty <code>String</code> is
* set
* @throws SQLException if a database access error occurs
* or the given column index is out of bounds
*/
public void setColumnLabel(int columnIndex, String label) throws SQLException {
checkColRange(columnIndex);
if (label != null) {
colInfo[columnIndex].columnLabel = label;
} else {
colInfo[columnIndex].columnLabel = "";
}
}
/**
* Sets the column name of the designated column to the given name.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param columnName a <code>String</code> object indicating the column name;
* if the given name is <code>null</code>, an empty <code>String</code>
* is set
* @throws SQLException if a database access error occurs or the given column
* index is out of bounds
*/
public void setColumnName(int columnIndex, String columnName) throws SQLException {
checkColRange(columnIndex);
if (columnName != null) {
colInfo[columnIndex].columnName = columnName;
} else {
colInfo[columnIndex].columnName = "";
}
}
/**
* Sets the designated column's table's schema name, if any, to
* <i>schemaName</i>. If <i>schemaName</i> is <code>null</code>,
* the schema name is set to an empty string ("").
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param schemaName the schema name for the table from which a value in the
* designated column was derived; may be an empty <code>String</code>
* or <code>null</code>
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public void setSchemaName(int columnIndex, String schemaName) throws SQLException {
checkColRange(columnIndex);
if (schemaName != null ) {
colInfo[columnIndex].schemaName = schemaName;
} else {
colInfo[columnIndex].schemaName = "";
}
}
/**
* Sets the total number of decimal digits in a value stored in the
* designated column to the given number.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param precision the total number of decimal digits; must be <code>0</code>
* or more
* @throws SQLException if a database access error occurs,
* <i>columnIndex</i> is out of bounds, or <i>precision</i>
* is less than <code>0</code>
*/
public void setPrecision(int columnIndex, int precision) throws SQLException {
if (precision < 0) {
throw new SQLException("Invalid precision value. Cannot be less " +
"than zero");
}
checkColRange(columnIndex);
colInfo[columnIndex].colPrecision = precision;
}
/**
* Sets the number of digits to the right of the decimal point in a value
* stored in the designated column to the given number.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param scale the number of digits to the right of the decimal point; must be
* zero or greater
* @throws SQLException if a database access error occurs,
* <i>columnIndex</i> is out of bounds, or <i>scale</i>
* is less than <code>0</code>
*/
public void setScale(int columnIndex, int scale) throws SQLException {
if (scale < 0) {
throw new SQLException("Invalid scale size. Cannot be less " +
"than zero");
}
checkColRange(columnIndex);
colInfo[columnIndex].colScale = scale;
}
/**
* Sets the name of the table from which the designated column
* was derived to the given table name.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param tableName the column's table name; may be <code>null</code> or an
* empty string
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public void setTableName(int columnIndex, String tableName) throws SQLException {
checkColRange(columnIndex);
if (tableName != null) {
colInfo[columnIndex].tableName = tableName;
} else {
colInfo[columnIndex].tableName = "";
}
}
/**
* Sets the catalog name of the table from which the designated
* column was derived to <i>catalogName</i>. If <i>catalogName</i>
* is <code>null</code>, the catalog name is set to an empty string.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param catalogName the column's table's catalog name; if the catalogName
* is <code>null</code>, an empty <code>String</code> is set
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public void setCatalogName(int columnIndex, String catalogName) throws SQLException {
checkColRange(columnIndex);
if (catalogName != null)
colInfo[columnIndex].catName = catalogName;
else
colInfo[columnIndex].catName = "";
}
/**
* Sets the SQL type code for values stored in the designated column
* to the given type code from the class <code>java.sql.Types</code>.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param SQLType the designated column's SQL type, which must be one of the
* constants in the class <code>java.sql.Types</code>
* @throws SQLException if a database access error occurs,
* the given column number is out of bounds, or the column type
* specified is not one of the constants in
* <code>java.sql.Types</code>
* @see java.sql.Types
*/
public void setColumnType(int columnIndex, int SQLType) throws SQLException {
// examine java.sql.Type reflectively, loop on the fields and check
// this. Separate out into a private method
checkColType(SQLType);
checkColRange(columnIndex);
colInfo[columnIndex].colType = SQLType;
}
/**
* Sets the type name used by the data source for values stored in the
* designated column to the given type name.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @param typeName the data source-specific type name; if <i>typeName</i> is
* <code>null</code>, an empty <code>String</code> is set
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public void setColumnTypeName(int columnIndex, String typeName)
throws SQLException {
checkColRange(columnIndex);
if (typeName != null) {
colInfo[columnIndex].colTypeName = typeName;
} else {
colInfo[columnIndex].colTypeName = "";
}
}
/**
* Retrieves the number of columns in the <code>RowSet</code> object
* for which this <code>RowSetMetaDataImpl</code> object was created.
*
* @return the number of columns
* @throws SQLException if an error occurs determining the column count
*/
public int getColumnCount() throws SQLException {
return colCount;
}
/**
* Retrieves whether a value stored in the designated column is
* automatically numbered, and thus readonly.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return <code>true</code> if the column is automatically numbered;
* <code>false</code> otherwise
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public boolean isAutoIncrement(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].autoIncrement;
}
/**
* Indicates whether the case of the designated column's name
* matters.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return <code>true</code> if the column name is case sensitive;
* <code>false</code> otherwise
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public boolean isCaseSensitive(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].caseSensitive;
}
/**
* Indicates whether a value stored in the designated column
* can be used in a <code>WHERE</code> clause.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return <code>true</code> if a value in the designated column can be used in a
* <code>WHERE</code> clause; <code>false</code> otherwise
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public boolean isSearchable(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].searchable;
}
/**
* Indicates whether a value stored in the designated column
* is a cash value.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return <code>true</code> if a value in the designated column is a cash value;
* <code>false</code> otherwise
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public boolean isCurrency(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].currency;
}
/**
* Retrieves a constant indicating whether it is possible
* to store a <code>NULL</code> value in the designated column.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return a constant from the <code>ResultSetMetaData</code> interface;
* either <code>columnNoNulls</code>,
* <code>columnNullable</code>, or
* <code>columnNullableUnknown</code>
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public int isNullable(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].nullable;
}
/**
* Indicates whether a value stored in the designated column is
* a signed number.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return <code>true</code> if if a value in the designated column is a signed
* number; <code>false</code> otherwise
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public boolean isSigned(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].signed;
}
/**
* Retrieves the normal maximum width in chars of the designated column.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return the maximum number of chars that can be displayed in the designated
* column
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public int getColumnDisplaySize(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].columnDisplaySize;
}
/**
* Retrieves the the suggested column title for the designated
* column for use in printouts and displays.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return the suggested column name to use in printouts and displays
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public String getColumnLabel(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].columnLabel;
}
/**
* Retrieves the name of the designated column.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return the column name of the designated column
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public String getColumnName(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].columnName;
}
/**
* Retrieves the schema name of the table from which the value
* in the designated column was derived.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns,
* inclusive
* @return the schema name or an empty <code>String</code> if no schema
* name is available
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public String getSchemaName(int columnIndex) throws SQLException {
checkColRange(columnIndex);
String str ="";
if(colInfo[columnIndex].schemaName == null){
} else {
str = colInfo[columnIndex].schemaName;
}
return str;
}
/**
* Retrieves the total number of digits for values stored in
* the designated column.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return the precision for values stored in the designated column
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public int getPrecision(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].colPrecision;
}
/**
* Retrieves the number of digits to the right of the decimal point
* for values stored in the designated column.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return the scale for values stored in the designated column
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public int getScale(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].colScale;
}
/**
* Retrieves the name of the table from which the value
* in the designated column was derived.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return the table name or an empty <code>String</code> if no table name
* is available
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public String getTableName(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].tableName;
}
/**
* Retrieves the catalog name of the table from which the value
* in the designated column was derived.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return the catalog name of the column's table or an empty
* <code>String</code> if no catalog name is available
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public String getCatalogName(int columnIndex) throws SQLException {
checkColRange(columnIndex);
String str ="";
if(colInfo[columnIndex].catName == null){
} else {
str = colInfo[columnIndex].catName;
}
return str;
}
/**
* Retrieves the type code (one of the <code>java.sql.Types</code>
* constants) for the SQL type of the value stored in the
* designated column.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return an <code>int</code> representing the SQL type of values
* stored in the designated column
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
* @see java.sql.Types
*/
public int getColumnType(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].colType;
}
/**
* Retrieves the DBMS-specific type name for values stored in the
* designated column.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return the type name used by the data source
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public String getColumnTypeName(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].colTypeName;
}
/**
* Indicates whether the designated column is definitely
* not writable, thus readonly.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return <code>true</code> if this <code>RowSet</code> object is read-Only
* and thus not updatable; <code>false</code> otherwise
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public boolean isReadOnly(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].readOnly;
}
/**
* Indicates whether it is possible for a write operation on
* the designated column to succeed. A return value of
* <code>true</code> means that a write operation may or may
* not succeed.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return <code>true</code> if a write operation on the designated column may
* will succeed; <code>false</code> otherwise
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public boolean isWritable(int columnIndex) throws SQLException {
checkColRange(columnIndex);
return colInfo[columnIndex].writable;
}
/**
* Indicates whether a write operation on the designated column
* will definitely succeed.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return <code>true</code> if a write operation on the designated column will
* definitely succeed; <code>false</code> otherwise
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public boolean isDefinitelyWritable(int columnIndex)
throws SQLException { return true;}
/**
* Retrieves the fully-qualified name of the class in the Java
* programming language to which a value in the designated column
* will be mapped. For example, if the value is an <code>int</code>,
* the class name returned by this method will be
* <code>java.lang.Integer</code>.
* <P>
* If the value in the designated column has a custom mapping,
* this method returns the name of the class that implements
* <code>SQLData</code>. When the method <code>ResultSet.getObject</code>
* is called to retrieve a value from the designated column, it will
* create an instance of this class or one of its subclasses.
*
* @param columnIndex the first column is 1, the second is 2, and so on;
* must be between <code>1</code> and the number of columns, inclusive
* @return the fully-qualified name of the class in the Java programming
* language that would be used by the method <code>RowSet.getObject</code> to
* retrieve the value in the specified column. This is the class
* name used for custom mapping when there is a custom mapping.
* @throws SQLException if a database access error occurs
* or the given column number is out of bounds
*/
public String getColumnClassName(int columnIndex) throws SQLException {
String className = String.class.getName();
int sqlType = getColumnType(columnIndex);
switch (sqlType) {
case Types.NUMERIC:
case Types.DECIMAL:
className = java.math.BigDecimal.class.getName();
break;
case Types.BIT:
className = java.lang.Boolean.class.getName();
break;
case Types.TINYINT:
className = java.lang.Byte.class.getName();
break;
case Types.SMALLINT:
className = java.lang.Short.class.getName();
break;
case Types.INTEGER:
className = java.lang.Integer.class.getName();
break;
case Types.BIGINT:
className = java.lang.Long.class.getName();
break;
case Types.REAL:
className = java.lang.Float.class.getName();
break;
case Types.FLOAT:
case Types.DOUBLE:
className = java.lang.Double.class.getName();
break;
case Types.BINARY:
case Types.VARBINARY:
case Types.LONGVARBINARY:
className = "byte[]";
break;
case Types.DATE:
className = java.sql.Date.class.getName();
break;
case Types.TIME:
className = java.sql.Time.class.getName();
break;
case Types.TIMESTAMP:
className = java.sql.Timestamp.class.getName();
break;
case Types.BLOB:
className = java.sql.Blob.class.getName();
break;
case Types.CLOB:
className = java.sql.Clob.class.getName();
break;
}
return className;
}
/**
* Returns an object that implements the given interface to allow access to non-standard methods,
* or standard methods not exposed by the proxy.
* The result may be either the object found to implement the interface or a proxy for that object.
* If the receiver implements the interface then that is the object. If the receiver is a wrapper
* and the wrapped object implements the interface then that is the object. Otherwise the object is
* the result of calling <code>unwrap</code> recursively on the wrapped object. If the receiver is not a
* wrapper and does not implement the interface, then an <code>SQLException</code> is thrown.
*
* @param iface A Class defining an interface that the result must implement.
* @return an object that implements the interface. May be a proxy for the actual implementing object.
* @throws java.sql.SQLException If no object found that implements the interface
* @since 1.6
*/
public <T> T unwrap(java.lang.Class<T> iface) throws java.sql.SQLException {
if(isWrapperFor(iface)) {
return iface.cast(this);
} else {
throw new SQLException("unwrap failed for:"+ iface);
}
}
/**
* Returns true if this either implements the interface argument or is directly or indirectly a wrapper
* for an object that does. Returns false otherwise. If this implements the interface then return true,
* else if this is a wrapper then return the result of recursively calling <code>isWrapperFor</code> on the wrapped
* object. If this does not implement the interface and is not a wrapper, return false.
* This method should be implemented as a low-cost operation compared to <code>unwrap</code> so that
* callers can use this method to avoid expensive <code>unwrap</code> calls that may fail. If this method
* returns true then calling <code>unwrap</code> with the same argument should succeed.
*
* @param interfaces a Class defining an interface.
* @return true if this implements the interface or directly or indirectly wraps an object that does.
* @throws java.sql.SQLException if an error occurs while determining whether this is a wrapper
* for an object with the given interface.
* @since 1.6
*/
public boolean isWrapperFor(Class<?> interfaces) throws SQLException {
return interfaces.isInstance(this);
}
static final long serialVersionUID = 6893806403181801867L;
private class ColInfo implements Serializable {
/**
* The field that indicates whether the value in this column is a number
* that is incremented automatically, which makes the value read-only.
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