Hibernate example source code file (Column.java)

This example Hibernate source code file (Column.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Hibernate tags/keywords

column, column, could, integer, integer, io, mapping, mappingexception, mappingexception, object, string, string, table, todo, value

The Hibernate Column.java source code

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2010, Red Hat Inc. or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Inc.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * This program 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 Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 */
package org.hibernate.mapping;
import java.io.Serializable;
import org.hibernate.HibernateException;
import org.hibernate.MappingException;
import org.hibernate.dialect.Dialect;
import org.hibernate.dialect.function.SQLFunctionRegistry;
import org.hibernate.engine.spi.Mapping;
import org.hibernate.sql.Template;
import org.hibernate.internal.util.StringHelper;

/**
 * A column of a relational database table
 * @author Gavin King
 */
public class Column implements Selectable, Serializable, Cloneable {

	public static final int DEFAULT_LENGTH = 255;
	public static final int DEFAULT_PRECISION = 19;
	public static final int DEFAULT_SCALE = 2;

	private int length=DEFAULT_LENGTH;
	private int precision=DEFAULT_PRECISION;
	private int scale=DEFAULT_SCALE;
	private Value value;
	private int typeIndex = 0;
	private String name;
	private boolean nullable=true;
	private boolean unique=false;
	private String sqlType;
	private Integer sqlTypeCode;
	private boolean quoted=false;
	int uniqueInteger;
	private String checkConstraint;
	private String comment;
	private String defaultValue;
	private String customWrite;
	private String customRead;

	public Column() {
	}

	public Column(String columnName) {
		setName(columnName);
	}

	public int getLength() {
		return length;
	}
	public void setLength(int length) {
		this.length = length;
	}
	public Value getValue() {
		return value;
	}
	public void setValue(Value value) {
		this.value= value;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		if (
			name.charAt(0)=='`' ||
			Dialect.QUOTE.indexOf( name.charAt(0) ) > -1 //TODO: deprecated, remove eventually
		) {
			quoted=true;
			this.name=name.substring( 1, name.length()-1 );
		}
		else {
			this.name = name;
		}
	}

	/** returns quoted name as it would be in the mapping file. */
	public String getQuotedName() {
		return quoted ?
				"`" + name + "`" :
				name;
	}

	public String getQuotedName(Dialect d) {
		return quoted ?
			d.openQuote() + name + d.closeQuote() :
			name;
	}
	
	/**
	 * For any column name, generate an alias that is unique
	 * to that column name, and also 10 characters or less
	 * in length.
	 */
	public String getAlias(Dialect dialect) {
		String alias = name;
		String unique = Integer.toString(uniqueInteger) + '_';
		int lastLetter = StringHelper.lastIndexOfLetter(name);
		if ( lastLetter == -1 ) {
			alias = "column";
		}
		else if ( lastLetter < name.length()-1 ) {
			alias = name.substring(0, lastLetter+1);
		}
		if ( alias.length() > dialect.getMaxAliasLength() ) {
			alias = alias.substring( 0, dialect.getMaxAliasLength() - unique.length() );
		}
		boolean useRawName = name.equals(alias) && 
			!quoted && 
			!name.toLowerCase().equals("rowid");
		if ( useRawName ) {
			return alias;
		}
		else {
			return alias + unique;
		}
	}
	
	/**
	 * Generate a column alias that is unique across multiple tables
	 */
	public String getAlias(Dialect dialect, Table table) {
		return getAlias(dialect) + table.getUniqueInteger() + '_';
	}

	public boolean isNullable() {
		return nullable;
	}

	public void setNullable(boolean nullable) {
		this.nullable=nullable;
	}

	public int getTypeIndex() {
		return typeIndex;
	}
	public void setTypeIndex(int typeIndex) {
		this.typeIndex = typeIndex;
	}

	public int getSqlTypeCode(Mapping mapping) throws MappingException {
		org.hibernate.type.Type type = getValue().getType();
		try {
			int sqlTypeCode = type.sqlTypes(mapping)[ getTypeIndex() ];
			if(getSqlTypeCode()!=null && getSqlTypeCode().intValue()!=sqlTypeCode) {
				throw new MappingException("SQLType code's does not match. mapped as " + sqlTypeCode + " but is " + getSqlTypeCode() );
			}
			return sqlTypeCode;
		}
		catch (Exception e) {
			throw new MappingException(
					"Could not determine type for column " +
					name +
					" of type " +
					type.getClass().getName() +
					": " +
					e.getClass().getName(),
					e
				);
		}
	}

	/**
	 * Returns the underlying columns sqltypecode.
	 * If null, it is because the sqltype code is unknown.
	 * 
	 * Use #getSqlTypeCode(Mapping) to retreive the sqltypecode used
	 * for the columns associated Value/Type.
	 * 
	 * @return sqltypecode if it is set, otherwise null.
	 */
	public Integer getSqlTypeCode() {
		return sqlTypeCode;
	}
	
	public void setSqlTypeCode(Integer typecode) {
		sqlTypeCode=typecode;
	}
	
	public boolean isUnique() {
		return unique;
	}


	public String getSqlType(Dialect dialect, Mapping mapping) throws HibernateException {
		return sqlType==null ?
			dialect.getTypeName( getSqlTypeCode(mapping), getLength(), getPrecision(), getScale() ) :
			sqlType;
	}

	public boolean equals(Object object) {
		return object instanceof Column && equals( (Column) object );
	}

	public boolean equals(Column column) {
		if (null == column) return false;
		if (this == column) return true;

		return isQuoted() ? 
			name.equals(column.name) :
			name.equalsIgnoreCase(column.name);
	}

	//used also for generation of FK names!
	public int hashCode() {
		return isQuoted() ? 
			name.hashCode() : 
			name.toLowerCase().hashCode();
	}

	public String getSqlType() {
		return sqlType;
	}

	public void setSqlType(String sqlType) {
		this.sqlType = sqlType;
	}

	public void setUnique(boolean unique) {
		this.unique = unique;
	}

	public boolean isQuoted() {
		return quoted;
	}

	public String toString() {
		return getClass().getName() + '(' + getName() + ')';
	}

	public String getCheckConstraint() {
		return checkConstraint;
	}

	public void setCheckConstraint(String checkConstraint) {
		this.checkConstraint = checkConstraint;
	}

	public boolean hasCheckConstraint() {
		return checkConstraint!=null;
	}

	public String getTemplate(Dialect dialect, SQLFunctionRegistry functionRegistry) {
		return hasCustomRead()
				? Template.renderWhereStringTemplate( customRead, dialect, functionRegistry )
				: Template.TEMPLATE + '.' + getQuotedName( dialect );
	}

	public boolean hasCustomRead() {
		return ( customRead != null && customRead.length() > 0 );
	}

	public String getReadExpr(Dialect dialect) {
		return hasCustomRead() ? customRead : getQuotedName( dialect );
	}
	
	public String getWriteExpr() {
		return ( customWrite != null && customWrite.length() > 0 ) ? customWrite : "?";
	}
	
	public boolean isFormula() {
		return false;
	}

	public String getText(Dialect d) {
		return getQuotedName(d);
	}
	public String getText() {
		return getName();
	}
	
	public int getPrecision() {
		return precision;
	}
	public void setPrecision(int scale) {
		this.precision = scale;
	}

	public int getScale() {
		return scale;
	}
	public void setScale(int scale) {
		this.scale = scale;
	}

	public String getComment() {
		return comment;
	}

	public void setComment(String comment) {
		this.comment = comment;
	}

	public String getDefaultValue() {
		return defaultValue;
	}

	public void setDefaultValue(String defaultValue) {
		this.defaultValue = defaultValue;
	}

	public String getCustomWrite() {
		return customWrite;
	}

	public void setCustomWrite(String customWrite) {
		this.customWrite = customWrite;
	}

	public String getCustomRead() {
		return customRead;
	}

	public void setCustomRead(String customRead) {
		this.customRead = customRead;
	}

	public String getCanonicalName() {
		return quoted ? name : name.toLowerCase();
	}

	/**
	 * Shallow copy, the value is not copied
	 */
	protected Object clone() {
		Column copy = new Column();
		copy.setLength( length );
		copy.setScale( scale );
		copy.setValue( value );
		copy.setTypeIndex( typeIndex );
		copy.setName( getQuotedName() );
		copy.setNullable( nullable );
		copy.setPrecision( precision );
		copy.setUnique( unique );
		copy.setSqlType( sqlType );
		copy.setSqlTypeCode( sqlTypeCode );
		copy.uniqueInteger = uniqueInteger; //usually useless
		copy.setCheckConstraint( checkConstraint );
		copy.setComment( comment );
		copy.setDefaultValue( defaultValue );
		copy.setCustomRead( customRead );
		copy.setCustomWrite( customWrite );
		return copy;
	}

}