org.apache.openjpa.jdbc.meta.strats.MultiColumnVersionStrategy Maven / Gradle / Ivy
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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.meta.strats;
import org.apache.commons.lang.StringUtils;
import org.apache.openjpa.jdbc.schema.Column;
import org.apache.openjpa.jdbc.schema.Schemas;
import org.apache.openjpa.meta.JavaTypes;
/**
* Uses multiple version numbers spanning multiple columns for optimistic
* versioning.
*
* @since 1.3.0
*
* @author Pinaki Poddar
*/
public class MultiColumnVersionStrategy extends NumberVersionStrategy {
public static final String ALIAS = "version-numbers";
private Number[] _initials = null;
private Integer[] _javaTypes;
@Override
public void initialize() {
if (_initials == null) {
Column[] cols = vers.getColumns();
_initials = new Number[cols.length];
for (int i = 0; i < cols.length; i++) {
_initials[i] = nextValue(0, getJavaType(i));
}
}
super.initialize();
}
/**
* Set the initial value for version columns. Defaults to 1 for each column.
*/
public void setInitialValues(Number[] initial) {
_initials = new Number[initial.length];
System.arraycopy(initial, 0, _initials, 0, initial.length);
}
/**
* Return the initial values for version columns. Defaults to 1 for each
* column.
*/
public Number[] getInitialValues() {
return _initials;
}
public String getAlias() {
return ALIAS;
}
protected int getJavaType() {
return JavaTypes.ARRAY;
}
protected int getJavaType(int i) {
if (_javaTypes == null) {
_javaTypes = new Integer[vers.getMappingInfo().getColumns().size()];
}
if (_javaTypes[i] == null) {
Column col = (Column)vers.getMappingInfo().getColumns().get(i);
if (!StringUtils.isEmpty(col.getTypeName())) {
Class javaType = Schemas.getJavaType(col.getType(),
col.getSize(), col.getDecimalDigits());
_javaTypes[i] = JavaTypes.getTypeCode(javaType);
} else {
_javaTypes[i] = JavaTypes.INT;
}
}
return _javaTypes[i];
}
protected Object nextVersion(Object version) {
if (version == null)
return _initials;
Object[] values = (Object[])version;
Number[] result = new Number[values.length];
for (int i = 0; i < values.length; i++)
result[i] = nextValue(values[i], getJavaType(i));
return result;
}
Number nextValue(Object number, int javaTypeCode) {
Number result = (number == null) ? 1 : ((Number)number).intValue() + 1;
return (Number)JavaTypes.convert(""+result, javaTypeCode);
}
}