com.jn.sqlhelper.dialect.internal.limit.AbstractLimitHandler Maven / Gradle / Ivy
package com.jn.sqlhelper.dialect.internal.limit;
import com.jn.sqlhelper.dialect.pagination.RowSelection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.List;
public abstract class AbstractLimitHandler extends LimitHandler {
protected int offsetBased = 0;
public void setOffsetBased(int offsetBased) {
this.offsetBased = offsetBased;
}
protected long convertToFirstRowValue(long zeroBasedFirstResult) {
return zeroBasedFirstResult + offsetBased;
}
@Override
public int bindLimitParametersAtStartOfQuery(RowSelection selection, PreparedStatement statement, int index)
throws SQLException {
return getDialect().isBindLimitParametersFirst() ? bindLimitParameters(selection, statement, index) : 0;
}
@Override
public int bindLimitParametersAtEndOfQuery(RowSelection selection, PreparedStatement statement, int index)
throws SQLException {
return !getDialect().isBindLimitParametersFirst() ? bindLimitParameters(selection, statement, index) : 0;
}
@Override
public int rebuildLimitParametersAtStartOfQuery(RowSelection selection, List queryParams, int index) {
return getDialect().isBindLimitParametersFirst() ? rebuildLimitParameters(selection, queryParams, index) : 0;
}
@Override
public int rebuildLimitParametersAtEndOfQuery(RowSelection selection, List queryParams, int index) {
return !getDialect().isBindLimitParametersFirst() ? rebuildLimitParameters(selection, queryParams, index) : 0;
}
@Override
public void setMaxRows(RowSelection selection, PreparedStatement statement)
throws SQLException {
if (selection.getMaxRows() >= 0) {
statement.setMaxRows(selection.getMaxRows());
}
}
private int bindLimitParameters(RowSelection selection, PreparedStatement statement, int index)
throws SQLException {
if ((!getDialect().isUseLimitInVariableMode()) || (!LimitHelper.hasMaxRows(selection))) {
return 0;
}
int firstRow = (int)convertToFirstRowValue(LimitHelper.getFirstRow(selection));
int lastRow = getMaxOrLimit(selection);
boolean hasFirstRow = getDialect().isSupportsLimitOffset() && ((firstRow > 0) || (getDialect().isForceLimitUsage()));
boolean reverse = getDialect().isBindLimitParametersInReverseOrder();
if (hasFirstRow) {
statement.setInt(index + (reverse ? 1 : 0), firstRow);
}
statement.setInt(index + ((reverse) || (!hasFirstRow) ? 0 : 1), lastRow);
return hasFirstRow ? 2 : 1;
}
private int rebuildLimitParameters(RowSelection selection, List queryParams, int index) {
if ((!getDialect().isUseLimitInVariableMode()) || (!LimitHelper.hasMaxRows(selection))) {
return 0;
}
int firstRow = (int)convertToFirstRowValue(LimitHelper.getFirstRow(selection));
int lastRow = getMaxOrLimit(selection);
boolean hasFirstRow = getDialect().isSupportsLimitOffset() && ((firstRow > 0) || (getDialect().isForceLimitUsage()));
boolean reverse = getDialect().isBindLimitParametersInReverseOrder();
int indexOfLastRow = index + ((reverse) || (!hasFirstRow) ? 0 : 1);
if (hasFirstRow) {
int indexOfFirstRow =index + (reverse ? 1 : 0);
if(indexOfFirstRow < indexOfLastRow){
queryParams.add(indexOfFirstRow, firstRow);
queryParams.add(indexOfLastRow, lastRow);
}else{
queryParams.add(indexOfLastRow, lastRow);
queryParams.add(indexOfFirstRow, firstRow);
}
}else {
queryParams.add(indexOfLastRow, lastRow);
}
return hasFirstRow ? 2 : 1;
}
protected final int getMaxOrLimit(RowSelection selection) {
long firstRow = convertToFirstRowValue(LimitHelper.getFirstRow(selection));
int limit = selection.getLimit();
return getDialect().isUseMaxForLimit() ? (limit + (int)firstRow) : limit;
}
}