package liquibase.sqlgenerator.core;

 import liquibase.database.Database;

 import liquibase.database.core.DB2Database;

 import liquibase.exception.ValidationErrors;

 import liquibase.sql.Sql;

 import liquibase.sql.UnparsedSql;

 import liquibase.sqlgenerator.SqlGenerator;

 import liquibase.sqlgenerator.SqlGeneratorChain;

 import liquibase.statement.core.FindForeignKeyConstraintsStatement;

 public class FindForeignKeyConstraintsGeneratorDB2 extends AbstractSqlGenerator<FindForeignKeyConstraintsStatement> {

     @Override

     public int getPriority() {

         return PRIORITY_DATABASE;

     }

     @Override

     public boolean supports(FindForeignKeyConstraintsStatement statement, Database database) {

         return database instanceof DB2Database;

     }

     public ValidationErrors validate(FindForeignKeyConstraintsStatement findForeignKeyConstraintsStatement,

             Database database, SqlGeneratorChain sqlGeneratorChain) {

         ValidationErrors validationErrors = new ValidationErrors();

         validationErrors.checkRequiredField("baseTableName", findForeignKeyConstraintsStatement.getBaseTableName());

         return validationErrors;

     }

     public Sql[] generateSql(FindForeignKeyConstraintsStatement statement, Database database,

             SqlGeneratorChain sqlGeneratorChain) {

         StringBuilder sb = new StringBuilder();

         sb.append("SELECT ");

         sb.append("TABNAME as ").append(FindForeignKeyConstraintsStatement.RESULT_COLUMN_BASE_TABLE_NAME).append(", ");

         sb.append("PK_COLNAMES as ").append(FindForeignKeyConstraintsStatement.RESULT_COLUMN_BASE_TABLE_COLUMN_NAME)

                 .append(", ");

         sb.append("REFTABNAME as ").append(FindForeignKeyConstraintsStatement.RESULT_COLUMN_FOREIGN_TABLE_NAME)

                 .append(", ");

         sb.append("FK_COLNAMES as ").append(FindForeignKeyConstraintsStatement.RESULT_COLUMN_FOREIGN_COLUMN_NAME)

                 .append(",");

         sb.append("CONSTNAME as ").append(FindForeignKeyConstraintsStatement.RESULT_COLUMN_CONSTRAINT_NAME).append(" ");

         sb.append("FROM SYSCAT.REFERENCES ");

         sb.append("WHERE TABNAME='").append(statement.getBaseTableName()).append("'");

         return new Sql[] { new UnparsedSql(sb.toString()) };

     }

 }