//$Id: NullableType.java 11046 2007-01-16 15:25:54Z steve.ebersole@jboss.com $
package org.hibernate.type;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.logging.Log;
import org.dom4j.Node;
import org.hibernate.EntityMode;
import org.hibernate.HibernateException;
import org.hibernate.engine.Mapping;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.engine.SessionImplementor;
import org.hibernate.util.ArrayHelper;
import org.hibernate.util.EqualsHelper;
import org.hibernate.util.StringHelper;
/**
* Superclass of single-column nullable types.
* @author Gavin King
*/
public abstract class NullableType extends AbstractType {
/**
* This is the old scheme where logging of parameter bindings and value extractions
* was controlled by the trace level enablement on the 'org.hibernate.type' package...
* <p/>
* Originally was cached such because of performance of looking up the logger each time
* in order to check the trace-enablement. Driving this via a central Log-specific class
* would alleviate that performance hit, and yet still allow more "normal" logging usage/config..
*/
private static final boolean IS_VALUE_TRACING_ENABLED = LogFactory.getLog( StringHelper.qualifier( Type.class.getName() ) ).isTraceEnabled();
private transient Log log;
private Log log() {
if ( log == null ) {
log = LogFactory.getLog( getClass() );
}
return log;
}
/**
* Get a column value from a result set, without worrying about the
* possibility of null values. Called from {@link #nullSafeGet} after
* nullness checks have been performed.
*
* @param rs The result set from which to extract the value.
* @param name The name of the value to extract.
*
* @return The extracted value.
*
* @throws org.hibernate.HibernateException Generally some form of mismatch error.
* @throws java.sql.SQLException Indicates problem making the JDBC call(s).
*/
public abstract Object get(ResultSet rs, String name) throws HibernateException, SQLException;
/**
* Set a parameter value without worrying about the possibility of null
* values. Called from {@link #nullSafeSet} after nullness checks have
* been performed.
*
* @param st The statement into which to bind the parameter value.
* @param value The parameter value to bind.
* @param index The position or index at which to bind the param value.
*
* @throws org.hibernate.HibernateException Generally some form of mismatch error.
* @throws java.sql.SQLException Indicates problem making the JDBC call(s).
*/
public abstract void set(PreparedStatement st, Object value, int index) throws HibernateException, SQLException;
/**
* A convenience form of {@link #sqlTypes(org.hibernate.engine.Mapping)}, returning
* just a single type value since these are explicitly dealing with single column
* mappings.
*
* @return The {@link java.sql.Types} mapping value.
*/
public abstract int sqlType();
/**
* A null-safe version of {@link #toString(Object)}. Specifically we are
* worried about null safeness in regards to the incoming value parameter,
* not the return.
*
* @param value The value to convert to a string representation; may be null.
* @return The string representation; may be null.
* @throws HibernateException Thrown by {@link #toString(Object)}, which this calls.
*/
public String nullSafeToString(Object value) throws HibernateException {
return value == null ? null : toString( value );
}
public abstract String toString(Object value) throws HibernateException;
public abstract Object fromStringValue(String xml) throws HibernateException;
public final void nullSafeSet(
PreparedStatement st,
Object value,
int index,
boolean[] settable,
SessionImplementor session) throws HibernateException, SQLException {
if ( settable[0] ) {
nullSafeSet(st, value, index);
}
}
public final void nullSafeSet(
PreparedStatement st,
Object value,
int index,
SessionImplementor session) throws HibernateException, SQLException {
nullSafeSet(st, value, index);
}
public final void nullSafeSet(
PreparedStatement st,
Object value,
int index) throws HibernateException, SQLException {
try {
if ( value == null ) {
if ( IS_VALUE_TRACING_ENABLED ) {
log().trace( "binding null to parameter: " + index );
}
st.setNull( index, sqlType() );
}
else {
if ( IS_VALUE_TRACING_ENABLED ) {
log().trace( "binding '" + toString( value ) + "' to parameter: " + index );
}
set( st, value, index );
}
}
catch ( RuntimeException re ) {
log().info( "could not bind value '" + nullSafeToString( value ) + "' to parameter: " + index + "; " + re.getMessage() );
throw re;
}
catch ( SQLException se ) {
log().info( "could not bind value '" + nullSafeToString( value ) + "' to parameter: " + index + "; " + se.getMessage() );
throw se;
}
}
public final Object nullSafeGet(
ResultSet rs,
String[] names,
SessionImplementor session,
Object owner) throws HibernateException, SQLException {
return nullSafeGet(rs, names[0]);
}
public final Object nullSafeGet(ResultSet rs, String[] names) throws HibernateException, SQLException {
return nullSafeGet(rs, names[0]);
}
public final Object nullSafeGet(ResultSet rs, String name) throws HibernateException, SQLException {
try {
Object value = get(rs, name);
if ( value == null || rs.wasNull() ) {
if ( IS_VALUE_TRACING_ENABLED ) {
log().trace( "returning null as column: " + name );
}
return null;
}
else {
if ( IS_VALUE_TRACING_ENABLED ) {
log().trace( "returning '" + toString( value ) + "' as column: " + name );
}
return value;
}
}
catch ( RuntimeException re ) {
log().info( "could not read column value from result set: " + name + "; " + re.getMessage() );
throw re;
}
catch ( SQLException se ) {
log().info( "could not read column value from result set: " + name + "; " + se.getMessage() );
throw se;
}
}
public final Object nullSafeGet(ResultSet rs, String name, SessionImplementor session, Object owner)
throws HibernateException, SQLException {
return nullSafeGet(rs, name);
}
public final String toXMLString(Object value, SessionFactoryImplementor pc)
throws HibernateException {
return toString(value);
}
public final Object fromXMLString(String xml, Mapping factory) throws HibernateException {
return xml==null || xml.length()==0 ? null : fromStringValue(xml);
}
public final int getColumnSpan(Mapping session) {
return 1;
}
public final int[] sqlTypes(Mapping session) {
return new int[] { sqlType() };
}
public final boolean isEqual(Object x, Object y, EntityMode entityMode) {
return isEqual(x, y);
}
public boolean isEqual(Object x, Object y) {
return EqualsHelper.equals(x, y);
}
public String toLoggableString(Object value, SessionFactoryImplementor factory) {
return value==null ? "null" : toString(value);
}
public Object fromXMLNode(Node xml, Mapping factory) throws HibernateException {
return fromXMLString( xml.getText(), factory );
}
public void setToXMLNode(Node xml, Object value, SessionFactoryImplementor factory)
throws HibernateException {
xml.setText( toXMLString(value, factory) );
}
public boolean[] toColumnNullness(Object value, Mapping mapping) {
return value==null ? ArrayHelper.FALSE : ArrayHelper.TRUE;
}
public boolean isDirty(Object old, Object current, boolean[] checkable, SessionImplementor session)
throws HibernateException {
return checkable[0] && isDirty(old, current, session);
}
}
|
