svn-gvsig-desktop / trunk / org.gvsig.desktop / org.gvsig.desktop.compat.cdc / org.gvsig.fmap.dal / org.gvsig.fmap.dal.db / org.gvsig.fmap.dal.db.jdbc / src / main / java / org / gvsig / fmap / dal / store / jdbc2 / spi / operations / TableIsEmptyOperation.java @ 44058
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package org.gvsig.fmap.dal.store.jdbc2.spi.operations; |
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import java.sql.Connection; |
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import java.sql.ResultSet; |
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import java.sql.SQLException; |
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import java.sql.Statement; |
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import org.apache.commons.lang3.StringUtils; |
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import org.gvsig.fmap.dal.exception.DataException; |
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import org.gvsig.fmap.dal.store.jdbc2.JDBCHelper; |
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import org.gvsig.fmap.dal.store.jdbc2.spi.JDBCSQLBuilderBase; |
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import org.gvsig.fmap.dal.store.jdbc.exception.JDBCSQLException; |
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import org.gvsig.fmap.dal.store.jdbc2.JDBCUtils; |
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import org.gvsig.fmap.dal.store.jdbc2.OperationsFactory.TableReference; |
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public class TableIsEmptyOperation extends AbstractConnectionOperation { |
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private final TableReference table; |
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private final String baseFilter; |
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private final String filter; |
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public TableIsEmptyOperation(
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JDBCHelper helper |
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) { |
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this(helper, null, null, null); |
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} |
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public TableIsEmptyOperation(
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JDBCHelper helper, |
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TableReference table, |
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String baseFilter,
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String filter
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) { |
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super(helper);
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this.table = table;
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this.baseFilter = baseFilter;
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this.filter = filter;
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} |
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@Override
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public final Object perform(Connection conn) throws DataException { |
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return this.tableIsEmpty(conn, table, baseFilter, filter); |
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} |
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public boolean tableIsEmpty(Connection conn, |
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TableReference table, |
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String baseFilter,
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String filter
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) throws DataException {
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JDBCSQLBuilderBase sqlbuilder = this.createSQLBuilder();
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sqlbuilder.select().column().all(); |
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sqlbuilder.select().from().table() |
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.database(this.table.getDatabase())
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.schema(this.table.getSchema())
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.name(this.table.getTable());
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sqlbuilder.select().from().subquery(this.table.getSubquery());
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if (!StringUtils.isEmpty(baseFilter)) {
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sqlbuilder.select().where().set( sqlbuilder.custom(baseFilter) ); |
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} |
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if (!StringUtils.isEmpty(filter)) {
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// El and() hace un set() si no hay un filtro previo
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sqlbuilder.select().where().and(sqlbuilder.custom(filter)); |
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} |
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sqlbuilder.select().limit(1);
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String sql = sqlbuilder.select().toString();
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Statement st = null; |
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ResultSet rs = null; |
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try {
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st = conn.createStatement(); |
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rs = JDBCUtils.executeQuery(st, sql); |
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return !rs.next();
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} catch (SQLException ex) { |
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throw new JDBCSQLException(ex); |
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} finally {
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JDBCUtils.closeQuietly(st); |
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JDBCUtils.closeQuietly(rs); |
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} |
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} |
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} |