package org.davidmoten.rx.jdbc.pool.internal;
   
   import java.sql.Connection;
   import java.sql.Statement;
   
   import io.reactivex.functions.Predicate;
   
   public final class HealthCheckPredicate implements Predicate<Connection> {
   
          private final String sql;
  
          public HealthCheckPredicate(String sql) {
              this.sql = sql;
          }
  
          @Override
          public boolean test(Connection c) throws Exception {
              try (Statement s = c.createStatement()) {
                  s.executeQuery(sql).close();
                  return true;
              } catch (Throwable t) {
                  return false;
              }
          }
      }