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/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.openjpa.jdbc.schema;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.sql.DatabaseMetaData;
import java.sql.Date;
import java.sql.Time;
import java.sql.Timestamp;
import java.sql.Types;
import java.util.HashSet;
import java.util.Set;
import org.apache.openjpa.jdbc.identifier.DBIdentifier;
import org.apache.openjpa.jdbc.identifier.QualifiedDBIdentifier;
import org.apache.openjpa.jdbc.meta.JavaSQLTypes;
import org.apache.openjpa.jdbc.meta.VersionStrategy;
import org.apache.openjpa.jdbc.sql.DBDictionary;
import org.apache.openjpa.lib.util.StringUtil;
import org.apache.openjpa.meta.JavaTypes;
/**
* Represents a database column. Closely aligned with the column
* information available from {@link DatabaseMetaData}.
*
* @author Abe White
* @author Stephen Kim
*/
public class Column extends ReferenceCounter {
private static final long serialVersionUID = 1L;
public static final int FLAG_UNINSERTABLE = 2 << 0;
public static final int FLAG_UNUPDATABLE = 2 << 1;
public static final int FLAG_DIRECT_INSERT = 2 << 2;
public static final int FLAG_DIRECT_UPDATE = 2 << 3;
public static final int FLAG_FK_INSERT = 2 << 4;
public static final int FLAG_FK_UPDATE = 2 << 5;
public static final int FLAG_PK_JOIN = 2 << 6;
private DBIdentifier _name = DBIdentifier.NULL;
private Table _table = null;
private DBIdentifier _tableName = DBIdentifier.NULL;
private DBIdentifier _schemaName = DBIdentifier.NULL;
private int _type = Types.OTHER;
private DBIdentifier _typeName = DBIdentifier.NULL;
private int _javaType = JavaTypes.OBJECT;
private int _size = 0;
private int _precision = -1;
private int _scale = -1;
private int _radix = 10;
private int _decimals = 0;
private String _defaultStr = null;
private Object _default = null;
private Boolean _notNull = null;
private boolean _autoAssign = false;
private boolean _rel = false;
private boolean _implicitRelation = false;
private DBIdentifier _target = DBIdentifier.NULL;
private String _targetField = null;
private int _flags = 0;
private QualifiedDBIdentifier _fullPath = null;
private int _index = 0;
private boolean _pk = false;
private VersionStrategy _versionStrategy = null;
private String _comment = null;
private boolean _XML = false;
private boolean _isUni1MFK = false;
private Set _constraints = new HashSet<>();
/**
* Default constructor.
*/
public Column() {
}
/**
* Constructor.
*
* @param name the name of the column
* @param table the column's table
* @deprecated
*/
@Deprecated
public Column(String name, Table table) {
this(DBIdentifier.newColumn(name), table);
}
public Column(DBIdentifier name, Table table) {
setIdentifier(name);
if (table != null) {
setTableIdentifier(table.getIdentifier());
setSchemaIdentifier(table.getSchemaIdentifier());
}
_table = table;
}
/**
* Called when the column is removed from its table. Removes the column
* from all table constraints and indexes, then invalidates it.
*/
void remove() {
Table table = getTable();
if (table == null)
return;
Schema schema = table.getSchema();
if (schema != null && schema.getSchemaGroup() != null) {
Schema[] schemas = schema.getSchemaGroup().getSchemas();
Table[] tabs;
ForeignKey[] fks;
Column[] cols;
Column[] pks;
for (Schema value : schemas) {
tabs = value.getTables();
for (Table tab : tabs) {
fks = tab.getForeignKeys();
for (ForeignKey fk : fks) {
cols = fk.getColumns();
pks = fk.getPrimaryKeyColumns();
for (int l = 0; l < cols.length; l++)
if (this.equals(cols[l]) || this.equals(pks[l]))
fk.removeJoin(cols[l]);
cols = fk.getConstantColumns();
for (Column col : cols)
if (this.equals(col))
fk.removeJoin(col);
pks = fk.getConstantPrimaryKeyColumns();
for (Column pk : pks)
if (this.equals(pk))
fk.removeJoin(pk);
if (fk.getColumns().length == 0
&& fk.getConstantColumns().length == 0)
tab.removeForeignKey(fk);
}
}
}
}
Index[] idxs = table.getIndexes();
for (Index idx : idxs)
if (idx.removeColumn(this) && idx.getColumns().length == 0)
table.removeIndex(idx);
Unique[] unqs = table.getUniques();
for (Unique unq : unqs)
if (unq.removeColumn(this) && unq.getColumns().length == 0)
table.removeUnique(unq);
PrimaryKey pk = table.getPrimaryKey();
if (pk != null && pk.removeColumn(this) && pk.getColumns().length == 0)
table.removePrimaryKey();
_table = null;
}
/**
* Return the table for the column.
*/
public Table getTable() {
return _table;
}
/**
* The column's table name.
* @deprecated
*/
@Deprecated
public String getTableName() {
return getTableIdentifier().getName();
}
public DBIdentifier getTableIdentifier() {
return _tableName == null ? DBIdentifier.NULL : _tableName;
}
/**
* The column's table name. You can only call this method on columns
* whose table object is not set.
* @deprecated
*/
@Deprecated
public void setTableName(String name) {
setTableIdentifier(DBIdentifier.newTable(name));
}
public void setTableIdentifier(DBIdentifier name) {
if (getTable() != null)
throw new IllegalStateException();
_tableName = name == null ? DBIdentifier.NULL : name;
_fullPath = null;
}
/**
* Reset the table name with the fully qualified table name which
* includes the schema name
* @deprecated
*/
@Deprecated
public void resetTableName(String name) {
_tableName = DBIdentifier.newTable(name);
}
public void resetTableIdentifier(DBIdentifier table) {
_tableName = table == null ? DBIdentifier.NULL : table;
}
/**
* The column's schema name.
* @deprecated
*/
@Deprecated
public String getSchemaName() {
return getSchemaIdentifier().getName();
}
public DBIdentifier getSchemaIdentifier() {
return _schemaName == null ? DBIdentifier.NULL : _schemaName;
}
/**
* The column's schema name. You can only call this method on columns
* whose table object is not set.
* @deprecated use setSchemaIdentifier(DBIdentifier name)
*/
@Deprecated
public void setSchemaName(String name) {
setSchemaIdentifier(DBIdentifier.newSchema(name));
}
public void setSchemaIdentifier(DBIdentifier name) {
if (getTable() != null)
throw new IllegalStateException();
_schemaName = name == null ? DBIdentifier.NULL : name;
}
/**
* Return the column's name.
* @deprecated use getIdentifier()
*/
@Deprecated
public String getName() {
return getIdentifier().getName();
}
public DBIdentifier getIdentifier() {
return _name == null ? DBIdentifier.NULL : _name;
}
/**
* Set the column's name. You can only call this method on columns
* whose table object is not set.
* @deprecated use setIdentifier(DBIdentifier name)
*/
@Deprecated
public void setName(String name) {
setIdentifier(DBIdentifier.newColumn(name));
}
public void setIdentifier(DBIdentifier name) {
if (getTable() != null)
throw new IllegalStateException();
_name = name == null ? DBIdentifier.NULL : name;
_fullPath = null;
}
/**
* Return the column's full name, in the form <table>.<name>.
* @deprecated use getFullDBIdentifier()
*/
@Deprecated
public String getFullName() {
return getFullDBIdentifier().getName();
}
public DBIdentifier getFullDBIdentifier() {
return getQualifiedPath().getIdentifier();
}
public QualifiedDBIdentifier getQualifiedPath() {
if (_fullPath == null) {
_fullPath = QualifiedDBIdentifier.newPath(getTableIdentifier(), getIdentifier() );
}
return _fullPath;
}
/**
* Return the column's SQL type. This will be one of the type constants
* defined in {@link Types}.
*/
public int getType() {
return _type;
}
/**
* Set the column's SQL type. This should be one of the type constants
* defined in {@link Types}.
*/
public void setType(int sqlType) {
_type = sqlType;
}
/**
* The database-specific SQL type of this column.
* @deprecated
*/
@Deprecated
public String getTypeName() {
return getTypeIdentifier().getName();
}
public DBIdentifier getTypeIdentifier() {
return _typeName == null ? DBIdentifier.NULL : _typeName ;
}
/**
* The database-specific SQL type of this column.
* @deprecated
*/
@Deprecated
public void setTypeName(String typeName) {
setTypeIdentifier(DBIdentifier.newColumnDefinition(typeName));
}
public void setTypeIdentifier(DBIdentifier typeName) {
_typeName = typeName == null ? DBIdentifier.NULL : typeName;
}
/**
* The Java type the data in this column is treated as, from
* {@link JavaTypes} or {@link JavaSQLTypes}.
*/
public int getJavaType() {
return _javaType;
}
/**
* The Java type the data in this column is treated as, from
* {@link JavaTypes} or {@link JavaSQLTypes}.
*/
public void setJavaType(int type) {
_javaType = type;
}
/**
* Return the column's size.
*/
public int getSize() {
return _size;
}
/**
* Set the column's size.
*/
public void setSize(int size) {
_size = size;
}
/**
* Return the number of decimal digits for the column, if applicable.
*/
public int getDecimalDigits() {
return _decimals;
}
/**
* Set the number of decimal digits for the column.
*/
public void setDecimalDigits(int digits) {
_decimals = digits;
}
public int getPrecision() {
return _precision;
}
public void setPrecision(int p) {
_precision = p;
}
public int getScale() {
return _scale;
}
public void setScale(int s) {
_scale = s;
}
public int getRadix() {
return _radix;
}
public void setRadix(int r) {
_radix = r;
}
/**
* Return the default value set for the column, if any.
*/
public String getDefaultString() {
return _defaultStr;
}
/**
* Set the default value for the column.
*/
public void setDefaultString(String def) {
_defaultStr = def;
_default = null;
}
/**
* Return the default value set for this column, if any. If only a default
* string has been set, attempts to convert it to the right type based
* on the Java type set for this column.
*/
public Object getDefault() {
if (_default != null)
return _default;
if (_defaultStr == null)
return null;
switch (_javaType) {
case JavaTypes.BOOLEAN:
case JavaTypes.BOOLEAN_OBJ:
_default = ("true".equals(_defaultStr)) ? Boolean.TRUE
: Boolean.FALSE;
break;
case JavaTypes.BYTE:
case JavaTypes.BYTE_OBJ:
_default = new Byte(_defaultStr);
break;
case JavaTypes.CHAR:
case JavaTypes.CHAR_OBJ:
_default = _defaultStr.charAt(0);
break;
case JavaTypes.DOUBLE:
case JavaTypes.DOUBLE_OBJ:
_default = new Double(_defaultStr);
break;
case JavaTypes.FLOAT:
case JavaTypes.FLOAT_OBJ:
_default = new Float(_defaultStr);
break;
case JavaTypes.INT:
case JavaTypes.INT_OBJ:
_default = Integer.parseInt(_defaultStr);
break;
case JavaTypes.LONG:
case JavaTypes.LONG_OBJ:
_default = Long.parseLong(_defaultStr);
break;
case JavaTypes.NUMBER:
case JavaTypes.BIGDECIMAL:
_default = new BigDecimal(_defaultStr);
break;
case JavaTypes.SHORT:
case JavaTypes.SHORT_OBJ:
_default = new Short(_defaultStr);
break;
case JavaTypes.DATE:
_default = new java.util.Date(_defaultStr);
break;
case JavaTypes.BIGINTEGER:
_default = new BigInteger(_defaultStr);
break;
case JavaSQLTypes.SQL_DATE:
_default = Date.valueOf(_defaultStr);
break;
case JavaSQLTypes.TIMESTAMP:
_default = Timestamp.valueOf(_defaultStr);
break;
case JavaSQLTypes.TIME:
_default = Time.valueOf(_defaultStr);
break;
default:
_default = _defaultStr;
}
return _default;
}
/**
* Set the default value for the column.
*/
public void setDefault(Object def) {
_default = def;
_defaultStr = (def == null) ? null : def.toString();
}
/**
* Return true if this is a NOT NULL column.
*/
public boolean isNotNull() {
return Boolean.TRUE.equals(_notNull);
}
/**
* Set whether this is a NOT NULL column.
*/
public void setNotNull(boolean notNull) {
_notNull = (notNull) ? Boolean.TRUE : Boolean.FALSE;
}
/**
* Whether the not-null property has been set.
*/
public boolean isNotNullExplicit() {
return _notNull != null;
}
/**
* Sets nullability of this receiver by the given flag.
* @param flag one of the JDBC nullability flag namely
* {@link DatabaseMetaData#columnNullableUnknown} : not known if the column can be set to null value
* {@link DatabaseMetaData#columnNullable} : the column can be set to null value
* {@link DatabaseMetaData#columnNoNulls} : the column can not be set to null value
*/
public void setNullability(short flag) {
switch (flag) {
case DatabaseMetaData.columnNullableUnknown : _notNull = null; break;
case DatabaseMetaData.columnNullable : _notNull = false; break;
case DatabaseMetaData.columnNoNulls : _notNull = true; break;
}
}
/**
* Whether this column is auto-assigned a value on insert.
*/
public boolean isAutoAssigned() {
return _autoAssign;
}
/**
* Whether this column is auto-incrementing.
*/
public void setAutoAssigned(boolean autoAssign) {
if (autoAssign != _autoAssign && getTable() != null)
getTable().changeAutoAssigned(this);
_autoAssign = autoAssign;
}
/**
* Whether this column stores some form of serialized identity value for
* a related record. This makes the column dependent on the knowing the
* final identity of the relation before the column value is set.
*/
public boolean isRelationId() {
return _rel;
}
/**
* Whether this column stores some form of serialized identity value for
* a related record. This makes the column dependent on the knowing the
* final identity of the relation before the column value is set.
*/
public void setRelationId(boolean rel) {
if (rel != _rel && getTable() != null)
getTable().changeRelationId(this);
_rel = rel;
}
/**
* The name of the column this column joins to, if any. Used for mapping.
* @deprecated use getTargetIdentifier()
*/
@Deprecated
public String getTarget() {
return getTargetIdentifier().getName();
}
public DBIdentifier getTargetIdentifier() {
return _target == null ? DBIdentifier.NULL : _target;
}
/**
* The name of the column this column joins to, if any. Used for mapping.
* @deprecated use setTargetIdentifier(DBIdentifier target)
*/
@Deprecated
public void setTarget(String target) {
setTargetIdentifier(DBIdentifier.newColumn(StringUtil.trimToNull(target)));
}
public void setTargetIdentifier(DBIdentifier target) {
_target = target == null ? DBIdentifier.NULL : DBIdentifier.trimToNull(target);
}
/**
* The name of the field this column joins to, if any. Used for mapping.
*/
public String getTargetField() {
return _targetField;
}
/**
* The name of the field this column joins to, if any. Used for mapping.
*/
public void setTargetField(String target) {
if (target != null && target.length() == 0)
target = null;
_targetField = target;
}
/**
* Flags are used for bookkeeping information. They are ignored at runtime.
*/
public boolean getFlag(int flag) {
return (_flags & flag) != 0;
}
/**
* Flags are used for bookkeeping information. They are ignored at runtime.
*/
public void setFlag(int flag, boolean on) {
if (on)
_flags |= flag;
else
_flags &= ~flag;
}
/**
* Return true if this column belongs to the table's primary key.
*/
public boolean isPrimaryKey() {
return _pk;
}
/**
* Set whether this column belongs to the table's primary key.
*/
void setPrimaryKey(boolean pk) {
_pk = pk;
}
/**
* Return the column's 0-based index in the owning table.
*/
public int getIndex() {
if (getTable() != null)
getTable().indexColumns();
return _index;
}
/**
* Set the column's 0-based index in the owning table.
*/
public void setIndex(int index) {
_index = index;
}
/**
* Whether this column is a LOB.
*/
public boolean isLob() {
switch (_type) {
case Types.BINARY:
case Types.BLOB:
case Types.LONGVARBINARY:
case Types.VARBINARY:
case Types.CLOB:
return true;
default:
return false;
}
}
/**
* Return true if this column is compatible with the given JDBC type
* from {@link Types} and size.
*/
public boolean isCompatible(int type, String typeName, int size,
int decimals) {
if (type == Types.OTHER || getType() == Types.OTHER)
return true;
// note that the given size is currently ignored, but may be useful
// to dynamically-populating subclasses
switch (getType()) {
case Types.BIT:
case Types.TINYINT:
case Types.BIGINT:
case Types.INTEGER:
case Types.NUMERIC:
case Types.SMALLINT:
case Types.DECIMAL:
case Types.DOUBLE:
case Types.FLOAT:
case Types.REAL:
switch (type) {
case Types.BIT:
case Types.TINYINT:
case Types.BIGINT:
case Types.INTEGER:
case Types.NUMERIC:
case Types.SMALLINT:
case Types.DECIMAL:
case Types.DOUBLE:
case Types.FLOAT:
case Types.REAL:
return true;
default:
return false;
}
case Types.BINARY:
case Types.BLOB:
case Types.LONGVARBINARY:
case Types.VARBINARY:
case Types.OTHER:
switch (type) {
case Types.BINARY:
case Types.BLOB:
case Types.LONGVARBINARY:
case Types.VARBINARY:
case Types.OTHER:
return true;
default:
return false;
}
case Types.CLOB:
case Types.CHAR:
case Types.LONGVARCHAR:
case Types.VARCHAR:
switch (type) {
case Types.CLOB:
case Types.CHAR:
case Types.LONGVARCHAR:
case Types.VARCHAR:
case Types.DATE:
case Types.TIME:
case Types.TIMESTAMP:
return true;
default:
return false;
}
case Types.DATE:
case Types.TIME:
case Types.TIMESTAMP:
switch (type) {
case Types.LONGVARCHAR:
case Types.CLOB:
case Types.VARCHAR:
case Types.DATE:
case Types.TIME:
case Types.TIMESTAMP:
case Types.TIMESTAMP_WITH_TIMEZONE:
return true;
default:
return false;
}
case Types.TIMESTAMP_WITH_TIMEZONE:
switch (type) {
case Types.DATE:
case Types.TIMESTAMP:
return true;
default:
return false;
}
case Types.TIME_WITH_TIMEZONE:
switch (type) {
case Types.DATE:
case Types.TIME:
case Types.TIMESTAMP:
return true;
default:
return false;
}
case Types.SQLXML: // All XML Types
case 2007: // Oracle-defined opaque type code for XMLType treated the same way
switch (type) {
case Types.CHAR:
case Types.LONGVARCHAR:
case Types.VARCHAR:
case Types.CLOB:
case Types.BLOB:
return true;
default:
return false;
}
default:
return type == getType();
}
}
/**
* Returns the column name.
*/
@Override
public String toString() {
return getIdentifier().getName();
}
/**
* Useful for debugging.
*/
public String getDescription() {
StringBuilder buf = new StringBuilder();
buf.append("Full Name: ").append(getFullName()).append("\n");
buf.append("Type: ").append(Schemas.getJDBCName(getType())).
append("\n");
buf.append("Size: ").append(getSize()).append("\n");
buf.append("Default: ").append(getDefaultString()).append("\n");
buf.append("Not Null: ").append(isNotNull()).append("\n");
return buf.toString();
}
/**
* Tests compatibility.
*/
public boolean equalsColumn(DBDictionary dict, Column col) {
if (col == this)
return true;
if (col == null)
return false;
if (!getQualifiedPath().equals(col.getQualifiedPath()))
return false;
if (!isCompatible(col.getType(), col.getTypeIdentifier().getName(), col.getSize(),
col.getDecimalDigits())) {
// do an additional lookup in case the java.sql.Types are different but
// they map to the same representation in the DB
if (dict.getTypeName(this).equals(dict.getTypeName(col))) {
return true;
}
return false;
}
if (getType() == Types.VARCHAR && getSize() > 0 && col.getSize() > 0
&& getSize() != col.getSize())
return false;
return true;
}
/**
* Copy information from the given column to this one.
*/
public void copy(Column from) {
if (from == null)
return;
if (DBIdentifier.isNull(getIdentifier()))
setIdentifier(from.getIdentifier());
if (getType() == Types.OTHER)
setType(from.getType());
if (DBIdentifier.isNull(getTypeIdentifier()))
setTypeIdentifier(from.getTypeIdentifier());
if (getJavaType() == JavaTypes.OBJECT)
setJavaType(from.getJavaType());
if (getSize() == 0)
setSize(from.getSize());
if (getDecimalDigits() == 0)
setDecimalDigits(from.getDecimalDigits());
if (getDefaultString() == null)
setDefaultString(from.getDefaultString());
if (!isNotNullExplicit() && from.isNotNullExplicit())
setNotNull(from.isNotNull());
if (!isAutoAssigned())
setAutoAssigned(from.isAutoAssigned());
if (!isRelationId())
setRelationId(from.isRelationId());
if (!isImplicitRelation())
setImplicitRelation(from.isRelationId());
if (DBIdentifier.isNull(getTargetIdentifier()))
setTargetIdentifier(from.getTargetIdentifier());
if (getTargetField() == null)
setTargetField(from.getTargetField());
if (_flags == 0)
_flags = from._flags;
if (!isXML())
setXML(from.isXML());
if (!isUni1MFK())
setUni1MFK(from.isUni1MFK());
for (Constraint c : _constraints) {
addConstraint(c);
}
}
/**
* Whether this column is of XML type.
*/
public boolean isXML() {
return _XML;
}
/**
* Whether this column is of XML type.
*/
public void setXML(boolean xml) {
_XML = xml;
}
public VersionStrategy getVersionStrategy() {
return _versionStrategy;
}
public void setVersionStrategy(VersionStrategy strategy) {
this._versionStrategy = strategy;
}
public boolean hasComment() {
return _comment != null && !_comment.equalsIgnoreCase(_name.toString());
}
public String getComment() {
return _comment;
}
public void setComment(String comment) {
_comment = comment;
}
/**
* Affirms if this instance represents an implicit relation. For example, a
* relation expressed as the value of primary key of the related class and
* not as object reference.
*
* @since 1.3.0
*/
public boolean isImplicitRelation() {
return _implicitRelation;
}
/**
* Sets a marker to imply a logical relation that can not have any physical
* manifest in the database. For example, a relation expressed as the value
* of primary key of the related class and not as object reference.
* Populated from @ForeignKey(implicit=true) annotation.
* The mutator can only transit from false to true but not vice versa.
*
* @since 1.3.0
*/
public void setImplicitRelation(boolean flag) {
_implicitRelation |= flag;
}
/**
* Sets a marker to indicate that this instance represents a uni-directional
* one to many relation using the foreign key strategy. This non-default
* mapping of uni-directional one-to-many is supported in JPA 2.0.
*
* @since 2.0
*/
public boolean isUni1MFK() {
return _isUni1MFK;
}
/**
* Affirms if this instance represents a uni-directional one to many relation
* using the foreign key strategy. This non-default mapping of uni-directional
* one-to-many is supported in JPA 2.0.
*
* @since 2.0
*/
public void setUni1MFK(boolean isUni1MFK) {
_isUni1MFK = isUni1MFK;
}
/**
* Adds the given constraint to this column.
*/
public void addConstraint(Constraint c) {
_constraints.add(c);
}
/**
* Removes the given constraint from this column.
*/
public void removeConstraint(Constraint c) {
_constraints.remove(c);
}
/**
* Affirms if this column has any constraint of given type.
*/
public boolean hasConstraint(Class type) {
return !getConstraints(type).isEmpty();
}
/**
* Gets all constrains attached this column.
*/
public Set getConstraints() {
return _constraints;
}
/**
* Gets all constrains of the given type attached to this column.
*/
public Set getConstraints(Class type) {
Set result = new HashSet<>();
for (Constraint c : _constraints) {
if (c.getClass() == type) {
result.add((T)c);
}
}
return result;
}
/**
* Affirms if any unique constraint is attached to this column.
*/
public boolean isUniqueConstraint() {
return hasConstraint(Unique.class);
}
/**
* Affirms if any index constraint is attached to this column.
*/
public boolean isIndex() {
return hasConstraint(Index.class);
}
/**
* Affirms if any foreign key constraint is attached to this column.
*/
public boolean isForeignKey() {
return hasConstraint(ForeignKey.class);
}
}