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Cayenne Object Persistence Framework

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package org.apache.cayenne.access.trans;

import org.apache.cayenne.map.DbEntity;
import org.apache.cayenne.map.DbRelationship;

/** Class implements default translation mechanism of org.apache.cayenne.query.DeleteQuery
 *  objects to SQL DELETE statements.
 *
 *  @author Andrei Adamchik
 */
public class DeleteTranslator extends QueryAssembler {

    public String aliasForTable(DbEntity dbEnt) {
        throw new RuntimeException("aliases not supported");
    }

    public void dbRelationshipAdded(DbRelationship dbRel) {
        throw new RuntimeException("db relationships not supported");
    }

    /** Main method of DeleteTranslator class. Translates DeleteQuery
     *  into a JDBC PreparedStatement
     */
    public String createSqlString() throws Exception {
        StringBuffer queryBuf = new StringBuffer("DELETE FROM ");

        // 1. append table name
        DbEntity dbEnt = getRootDbEntity();
        queryBuf.append(dbEnt.getFullyQualifiedName());

        // 2. build qualifier
        String qualifierStr =
            adapter.getQualifierTranslator(this).doTranslation();
        if (qualifierStr != null)
            queryBuf.append(" WHERE ").append(qualifierStr);

        return queryBuf.toString();
    }
}