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package com.nordstrom.common.jdbc;

import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Objects;
import java.util.ServiceLoader;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import com.nordstrom.common.base.UncheckedThrow;
import com.nordstrom.common.jdbc.Param.Mode;

import java.sql.PreparedStatement;

/**
 * This utility class provides facilities that enable you to define collections of database queries and stored
 * procedures in an easy-to-execute format.
 * 

* Query collections are defined as Java enumerations that implement the {@link QueryAPI} * interface: *

    *
  • {@link QueryAPI#getQueryStr() getQueryStr} - Get the query string for this constant. This is the actual query * that's sent to the database.
  • *
  • {@link QueryAPI#getArgNames() getArgNames} - Get the names of the arguments for this query. This provides * diagnostic information if the incorrect number of arguments is specified by the client.
  • *
  • {@link QueryAPI#getConnection() getConnection} - Get the connection string associated with this query. This * eliminates the need for the client to provide this information.
  • *
  • {@link QueryAPI#getEnum() getEnum} - Get the enumeration to which this query belongs. This enables {@link * #executeQuery(Class, QueryAPI, Object[])} to retrieve the name of the query's enumerated constant for * diagnostic messages.
  • *
*

* Store procedure collections are defined as Java enumerations that implement the {@link SProcAPI} * interface: *

    *
  • {@link SProcAPI#getSignature() getSignature} - Get the signature for this stored procedure object. This defines * the name of the stored procedure and the modes of its arguments. If the stored procedure accepts varargs, this * will also be indicated.
  • *
  • {@link SProcAPI#getArgTypes() getArgTypes} - Get the argument types for this stored procedure object.
  • *
  • {@link SProcAPI#getConnection() getConnection} - Get the connection string associated with this stored * procedure. This eliminates the need for the client to provide this information.
  • *
  • {@link SProcAPI#getEnum() getEnum} - Get the enumeration to which this stored procedure belongs. This enables * {@link #executeStoredProcedure(Class, SProcAPI, Object[])} to retrieve the name of the stored procedured's * enumerated constant for diagnostic messages.
  • *
*

* To maximize usability and configurability, we recommend the following implementation strategy:

    *
  • Define your collection as an enumeration:
      *
    • Query collections implement {@link QueryAPI}.
    • *
    • Stored procedure collections implement {@link SProcAPI}.
    • *
  • *
  • Define each constant:
      *
    • (query) Specify a property name and a name for each argument (if any).
    • *
    • (sproc) Declare the signature and the type for each argument (if any).
    • *
  • *
  • To assist users of your queries, preface their names with a type indicator (GET or UPDATE).
  • *
  • Back query collections with configurations that implement the {@code Settings API}:
      *
    • groupId: com.nordstrom.test-automation.tools
    • *
    • artifactId: settings
    • *
    • className: com.nordstrom.automation.settings.SettingsCore
    • *
  • *
  • To support execution on multiple endpoints, implement {@link QueryAPI#getConnection()} or {@link * SProcAPI#getConnection()} with sub-configurations or other dynamic data sources (e.g. * - web service).
  • *
* Query Collection Example * *
 * public class OpctConfig extends {@code SettingsCore} {
 * 
 *     private static final String SETTINGS_FILE = "OpctConfig.properties";
 * 
 *     private OpctConfig() throws ConfigurationException, IOException {
 *         super(OpctValues.class);
 *     }
 * 
 *     public enum OpctValues implements SettingsCore.SettingsAPI, QueryAPI {
 *         /** args: [  ] */
 *         GET_RULE_HEAD_DETAILS("opct.query.getRuleHeadDetails"),
 *         /** args: [ name, zone_id, priority, rule_type ] */
 *         GET_RULE_COUNT("opct.query.getRuleCount", "name", "zone_id", "priority", "rule_type"),
 *         /** args: [ role_id, user_id ] */
 *         UPDATE_USER_ROLE("opct.query.updateRsmUserRole", "role_id", "user_id"),
 *         /** MST connection string */
 *         MST_CONNECT("opct.connect.mst"),
 *         /** RMS connection string */
 *         RMS_CONNECT("opct.connect.rms");
 * 
 *         private String key;
 *         private String[] args;
 *         private String query;
 * 
 *         private static OpctConfig config;
 *         private static String mstConnect;
 *         private static String rmsConnect;
 * 
 *         private static {@code EnumSet} rmsQueries = EnumSet.of(UPDATE_USER_ROLE);
 * 
 *         static {
 *             try {
 *                 config = new OpctConfig();
 *             } catch (ConfigurationException | IOException e) {
 *                 throw new RuntimeException("Unable to instantiate OPCT configuration object", e);
 *             }
 *         }
 * 
 *         OpctValues(String key, String... args) {
 *             this.key = key;
 *             this.args = args;
 *         }
 * 
 *         {@code @Override}
 *         public String key() {
 *             return key;
 *         }
 * 
 *         {@code @Override}
 *         public String getQueryStr() {
 *             if (query == null) {
 *                 query = config.getString(key);
 *             }
 *             return query;
 *         }
 * 
 *         {@code @Override}
 *         public String[] getArgNames() {
 *             return args;
 *         }
 * 
 *         {@code @Override}
 *         public String getConnection() {
 *             if (rmsQueries.contains(this)) {
 *                 return getRmsConnect();
 *             } else {
 *                 return getMstConnect();
 *             }
 *         }
 * 
 *         {@code @Override}
 *         public {@code Enum} getEnum() {
 *             return this;
 *         }
 * 
 *         /**
 *          * Get MST connection string.
 *          * 
 *          * @return MST connection string
 *          */
 *         public static String getMstConnect() {
 *             if (mstConnect == null) {
 *                 mstConnect = config.getString(OpctValues.MST_CONNECT.key());
 *             }
 *             return mstConnect;
 *         }
 * 
 *         /**
 *          * Get RMS connection string.
 *          * 
 *          * @return RMS connection string
 *          */
 *         public static String getRmsConnect() {
 *             if (rmsConnect == null) {
 *                 rmsConnect = config.getString(OpctValues.RMS_CONNECT.key());
 *             }
 *             return rmsConnect;
 *         }
 *     }
 * 
 *     {@code @Override}
 *     public String getSettingsPath() {
 *         return SETTINGS_FILE;
 *     }
 * 
 *     /**
 *      * Get OPCT configuration object.
 *      *
 *      * @return OPCT configuration object
 *      */
 *     public static OpctConfig getConfig() {
 *         return OpctValues.config;
 *     }
 * 
 *     public enum SProcValues implements SProcAPI {
 *         /** args: [  ] */
 *         SHOW_SUPPLIERS("SHOW_SUPPLIERS()"),
 *         /** args: [ coffee_name, supplier_name ] */
 *         GET_SUPPLIER_OF_COFFEE("GET_SUPPLIER_OF_COFFEE(>, <)", Types.VARCHAR, Types.VARCHAR),
 *         /** args: [ coffee_name, max_percent, new_price ] */
 *         RAISE_PRICE("RAISE_PRICE(>, >, =)", Types.VARCHAR, Types.REAL, Types.NUMERIC),
 *         /** args: [ str, val... ] */
 *         IN_VARARGS("IN_VARARGS(<, >:)", Types.VARCHAR, Types.INTEGER),
 *         /** args: [ val, str... ] */
 *         OUT_VARARGS("OUT_VARARGS(>, <:)", Types.INTEGER, Types.VARCHAR);
 * 
 *         private int[] argTypes;
 *         private String signature;
 * 
 *         SProcValues(String signature, int... argTypes) {
 *             this.signature = signature;
 *             
 *             this.argTypes = argTypes;
 *         }
 * 
 *         {@code @Override}
 *         public String getSignature() {
 *             return signature;
 *         }
 * 
 *         {@code @Override}
 *         public int[] getArgTypes () {
 *             return argTypes;
 *         }
 * 
 *         {@code @Override}
 *         public String getConnection() {
               return OpctValues.getRmsConnect();
 *         }
 * 
 *         {@code @Override}
 *         public {@code Enum} getEnum() {
 *             return this;
 *         }
 *     }
 * }
 * 
*/ public class DatabaseUtils { private static Pattern SPROC_PATTERN = Pattern.compile("([\\p{Alpha}_][\\p{Alpha}\\p{Digit}@$#_]*)(?:\\(([<>=](?:,\\s*[<>=])*)?(:)?\\))?"); private DatabaseUtils() { throw new AssertionError("DatabaseUtils is a static utility class that cannot be instantiated"); } static { Iterator iterator = ServiceLoader.load(Driver.class).iterator(); while (iterator.hasNext()) { iterator.next(); } } /** * Execute the specified query object with supplied arguments as an 'update' operation * * @param query query object to execute * @param queryArgs replacement values for query place-holders * @return count of records updated */ public static int update(QueryAPI query, Object... queryArgs) { Integer result = (Integer) executeQuery(null, query, queryArgs); return (result != null) ? result.intValue() : -1; } /** * Execute the specified query object with supplied arguments as a 'query' operation * * @param query query object to execute * @param queryArgs replacement values for query place-holders * @return row 1 / column 1 as integer; -1 if no rows were returned */ public static int getInt(QueryAPI query, Object... queryArgs) { Integer result = (Integer) executeQuery(Integer.class, query, queryArgs); return (result != null) ? result.intValue() : -1; } /** * Execute the specified query object with supplied arguments as a 'query' operation * * @param query query object to execute * @param queryArgs replacement values for query place-holders * @return row 1 / column 1 as string; {@code null} if no rows were returned */ public static String getString(QueryAPI query, Object... queryArgs) { return (String) executeQuery(String.class, query, queryArgs); } /** * Execute the specified query object with supplied arguments as a 'query' operation * * @param query query object to execute * @param queryArgs replacement values for query place-holders * @return {@link ResultPackage} object */ public static ResultPackage getResultPackage(QueryAPI query, Object... queryArgs) { return (ResultPackage) executeQuery(ResultPackage.class, query, queryArgs); } /** * Execute the specified query with the supplied arguments, returning a result of the indicated type. *

* TYPES: Specific result types produce the following behaviors:

    *
  • {@code null} - The query is executed as an update operation.
  • *
  • {@link ResultPackage} - An object containing the connection, statement, and result set is returned
  • *
  • {@link Integer} - If rows were returned, row 1 / column 1 is returned as an Integer; otherwise -1
  • *
  • {@link String} - If rows were returned, row 1 / column 1 is returned as an String; otherwise {@code null}
  • *
  • For other types, {@link ResultSet#getObject(int, Class)} to return row 1 / column 1 as that type
* * @param resultType desired result type (see TYPES above) * @param query query object to execute * @param queryArgs replacement values for query place-holders * @return for update operations, the number of rows affected; for query operations, an object of the indicated type
* NOTE: If you specify {@link ResultPackage} as the result type, it's recommended that you close this object * when you're done with it to free up database and JDBC resources that were allocated for it. */ private static Object executeQuery(Class resultType, QueryAPI query, Object... queryArgs) { int expectCount = query.getArgNames().length; int actualCount = queryArgs.length; if (actualCount != expectCount) { String message; if (expectCount == 0) { message = "No arguments expected for " + query.getEnum().name(); } else { message = String.format("Incorrect argument count for %s%s: expect: %d; actual: %d", query.getEnum().name(), Arrays.toString(query.getArgNames()), expectCount, actualCount); } throw new IllegalArgumentException(message); } return executeQuery(resultType, query.getConnection(), query.getQueryStr(), queryArgs); } /** * Execute the specified query with the supplied arguments, returning a result of the indicated type. *

* TYPES: Specific result types produce the following behaviors:

    *
  • {@code null} - The query is executed as an update operation.
  • *
  • {@link ResultPackage} - An object containing the connection, statement, and result set is returned
  • *
  • {@link Integer} - If rows were returned, row 1 / column 1 is returned as an Integer; otherwise -1
  • *
  • {@link String} - If rows were returned, row 1 / column 1 is returned as an String; otherwise {@code null}
  • *
  • For other types, {@link ResultSet#getObject(int, Class)} to return row 1 / column 1 as that type
* * @param resultType desired result type (see TYPES above) * @param connectionStr database connection string * @param queryStr a SQL statement that may contain one or more '?' IN parameter placeholders * @param params an array of objects containing the input parameter values * @return for update operations, the number of rows affected; for query operations, an object of the indicated type
* NOTE: If you specify {@link ResultPackage} as the result type, it's recommended that you close this object * when you're done with it to free up database and JDBC resources that were allocated for it. */ public static Object executeQuery(Class resultType, String connectionStr, String queryStr, Object... params) { try { Connection connection = getConnection(connectionStr); PreparedStatement statement = connection.prepareStatement(queryStr); for (int i = 0; i < params.length; i++) { statement.setObject(i + 1, params[i]); } return executeStatement(resultType, connection, statement); } catch (SQLException e) { throw UncheckedThrow.throwUnchecked(e); } } /** * Execute the specified stored procedure object with supplied parameters * * @param sproc stored procedure object to execute * @param params an array of objects containing the input parameter values * @return row 1 / column 1 as integer; -1 if no rows were returned */ public static int getInt(SProcAPI sproc, Object... params) { Integer result = (Integer) executeStoredProcedure(Integer.class, sproc, params); return (result != null) ? result.intValue() : -1; } /** * Execute the specified stored procedure object with supplied parameters * * @param sproc stored procedure object to execute * @param params an array of objects containing the input parameter values * @return row 1 / column 1 as string; {@code null} if no rows were returned */ public static String getString(SProcAPI sproc, Object... params) { return (String) executeStoredProcedure(String.class, sproc, params); } /** * Execute the specified stored procedure object with supplied parameters * * @param sproc stored procedure object to execute * @param params an array of objects containing the input parameter values * @return {@link ResultPackage} object */ public static ResultPackage getResultPackage(SProcAPI sproc, Object... params) { return (ResultPackage) executeStoredProcedure(ResultPackage.class, sproc, params); } /** * Execute the specified stored procedure with the specified arguments, returning a result of the indicated type. *

* TYPES: Specific result types produce the following behaviors:

    *
  • {@link ResultPackage} - An object containing the connection, statement, and result set is returned
  • *
  • {@link Integer} - If rows were returned, row 1 / column 1 is returned as an Integer; otherwise -1
  • *
  • {@link String} - If rows were returned, row 1 / column 1 is returned as an String; otherwise {@code null}
  • *
  • For other types, {@link ResultSet#getObject(int, Class)} to return row 1 / column 1 as that type
* * @param resultType desired result type (see TYPES above) * @param sproc stored procedure object to execute * @param params an array of objects containing the input parameter values * @return an object of the indicated type
* NOTE: If you specify {@link ResultPackage} as the result type, it's recommended that you close this object * when you're done with it to free up database and JDBC resources that were allocated for it. */ public static Object executeStoredProcedure(Class resultType, SProcAPI sproc, Object... params) { Objects.requireNonNull(resultType, "[resultType] argument must be non-null"); String[] args = {}; String sprocName = null; boolean hasVarArgs = false; int[] argTypes = sproc.getArgTypes(); String signature = sproc.getSignature(); Matcher matcher = SPROC_PATTERN.matcher(signature); String message = null; if (matcher.matches()) { sprocName = matcher.group(1); hasVarArgs = (matcher.group(3) != null); if (matcher.group(2) != null) { args = matcher.group(2).split(",\\s"); } else { if (hasVarArgs) { message = String.format("VarArgs indicated with no placeholder in signature for %s: %s", sproc.getEnum().name(), signature); } } } else { message = String.format("Unsupported stored procedure signature for %s: %s", sproc.getEnum().name(), signature); } if (message != null) { throw new IllegalArgumentException(message); } int argsCount = args.length; int typesCount = argTypes.length; int parmsCount = params.length; int minCount = typesCount; // if unbalanced args/types if (argsCount != typesCount) { message = String.format( "Signature argument count differs from declared type count for %s%s: " + "signature: %d; declared: %d", sproc.getEnum().name(), Arrays.toString(argTypes), argsCount, typesCount); } else if (hasVarArgs) { minCount -= 1; if (parmsCount < minCount) { message = String.format( "Insufficient arguments count for %s%s: minimum: %d; actual: %d", sproc.getEnum().name(), Arrays.toString(argTypes), minCount, parmsCount); } } else if (parmsCount != typesCount) { if (typesCount == 0) { message = "No arguments expected for " + sproc.getEnum().name(); } else { message = String.format( "Incorrect arguments count for %s%s: expect: %d; actual: %d", sproc.getEnum().name(), Arrays.toString(argTypes), typesCount, parmsCount); } } if (message != null) { throw new IllegalArgumentException(message); } Param[] parmArray = Param.array(parmsCount); int i; // process declared parameters for (i = 0; i < minCount; i++) { Mode mode = Mode.fromChar(args[i].charAt(0)); parmArray[i] = Param.create(mode, argTypes[i], params[i]); } // handle varargs parameters for (int j = i; j < parmsCount; j++) { Mode mode = Mode.fromChar(args[i].charAt(0)); parmArray[j] = Param.create(mode, argTypes[i], params[j]); } return executeStoredProcedure(resultType, sproc.getConnection(), sprocName, parmArray); } /** * Execute the specified stored procedure with the supplied arguments, returning a result of the indicated type. *

* TYPES: Specific result types produce the following behaviors:

    *
  • {@link ResultPackage} - An object containing the connection, statement, and result set is returned
  • *
  • {@link Integer} - If rows were returned, row 1 / column 1 is returned as an Integer; otherwise -1
  • *
  • {@link String} - If rows were returned, row 1 / column 1 is returned as an String; otherwise {@code null}
  • *
  • For other types, {@link ResultSet#getObject(int, Class)} to return row 1 / column 1 as that type
* * @param resultType desired result type (see TYPES above) * @param connectionStr database connection string * @param sprocName name of the stored procedure to be executed * @param params an array of objects containing the input parameter values * @return an object of the indicated type
* NOTE: If you specify {@link ResultPackage} as the result type, it's recommended that you close this object * when you're done with it to free up database and JDBC resources that were allocated for it. */ public static Object executeStoredProcedure(Class resultType, String connectionStr, String sprocName, Param... params) { Objects.requireNonNull(resultType, "[resultType] argument must be non-null"); StringBuilder sprocStr = new StringBuilder("{call ").append(sprocName).append("("); String placeholder = "?"; for (int i = 0; i < params.length; i++) { sprocStr.append(placeholder); placeholder = ",?"; } sprocStr.append(")}"); try { Connection connection = getConnection(connectionStr); CallableStatement statement = connection.prepareCall(sprocStr.toString()); for (int i = 0; i < params.length; i++) { params[i].set(statement, i + 1); } return executeStatement(resultType, connection, statement); } catch (SQLException e) { throw UncheckedThrow.throwUnchecked(e); } } /** * Execute the specified prepared statement, returning a result of the indicated type. *

* TYPES: Specific result types produce the following behaviors:

    *
  • {@code null} - The prepared statement is a query to be executed as an update operation.
  • *
  • {@link ResultPackage} - An object containing the connection, statement, and result set is returned
  • *
  • {@link Integer} - If rows were returned, row 1 / column 1 is returned as an Integer; otherwise -1
  • *
  • {@link String} - If rows were returned, row 1 / column 1 is returned as an String; otherwise {@code null}
  • *
  • For other types, {@link ResultSet#getObject(int, Class)} to return row 1 / column 1 as that type
*

* NOTE: For all result types except {@link ResultPackage}, the specified connection and statement, as well * as the result set from executing the statement, are closed prior to returning the result. * * @param resultType desired result type (see TYPES above) * @param connectionStr database connection string * @param statement prepared statement to be executed (query or store procedure) * @return for update operations, the number of rows affected; for query operations, an object of the indicated type
* NOTE: If you specify {@link ResultPackage} as the result type, it's recommended that you close this object * when you're done with it to free up database and JDBC resources that were allocated for it. */ private static Object executeStatement(Class resultType, Connection connection, PreparedStatement statement) { Object result = null; boolean failed = false; ResultSet resultSet = null; try { if (resultType == null) { result = Integer.valueOf(statement.executeUpdate()); } else { if (statement instanceof CallableStatement) { if (statement.execute()) { resultSet = statement.getResultSet(); //NOSONAR } if (resultType == ResultPackage.class) { result = new ResultPackage(connection, statement, resultSet); //NOSONAR } else if (resultType == Integer.class) { result = ((CallableStatement) statement).getInt(1); } else if (resultType == String.class) { result = ((CallableStatement) statement).getString(1); } else { result = ((CallableStatement) statement).getObject(1); } } else { resultSet = statement.executeQuery(); //NOSONAR if (resultType == ResultPackage.class) { result = new ResultPackage(connection, statement, resultSet); //NOSONAR } else if (resultType == Integer.class) { result = Integer.valueOf((resultSet.next()) ? resultSet.getInt(1) : -1); } else if (resultType == String.class) { result = (resultSet.next()) ? resultSet.getString(1) : null; } else { result = (resultSet.next()) ? resultSet.getObject(1, resultType) : null; } } } } catch (SQLException e) { failed = true; throw UncheckedThrow.throwUnchecked(e); } finally { if (failed || (resultType != ResultPackage.class)) { if (resultSet != null) { try { resultSet.close(); } catch (SQLException e) { // Suppress shutdown failures } } if (statement != null) { try { statement.close(); } catch (SQLException e) { // Suppress shutdown failures } } if (connection != null) { try { connection.commit(); connection.close(); } catch (SQLException e) { // Suppress shutdown failures } } } } return result; } /** * Get a connection to the database associated with the specified connection string. * * @param connectionString database connection string * @return database connection object */ private static Connection getConnection(String connectionString) { try { return DriverManager.getConnection(connectionString); } catch (SQLException e) { throw UncheckedThrow.throwUnchecked(e); } } /** * This interface defines the API supported by database query collections */ public interface QueryAPI { /** * Get the query string for this query object. * * @return query object query string */ String getQueryStr(); /** * Get the argument names for this query object. * * @return query object argument names */ String[] getArgNames(); /** * Get the database connection string for this query object. * * @return query object connection string */ String getConnection(); /** * Get the implementing enumerated constant for this query object. * * @return query object enumerated constant */ Enum getEnum(); //NOSONAR } /** * This interface defines the API supported by database stored procedure collections */ public interface SProcAPI { /** * Get the signature for this stored procedure object. *

* Each argument place holder in the stored procedure signature indicates the mode of the corresponding * parameter: * *

    *
  • '>' : This argument is an IN parameter
  • *
  • '<' : This argument is an OUT parameter
  • *
  • '=' : This argument is an INOUT parameter
  • *
* * For example: * *
RAISE_PRICE(>, <, =)
* * The first and second arguments are IN parameters, and the third argument is an INOUT parameter. * * @return stored procedure signature */ String getSignature(); /** * Get the argument types for this stored procedure object. * * @return stored procedure argument types */ int[] getArgTypes(); /** * Get the database connection string for this stored procedure object. * * @return stored procedure connection string */ String getConnection(); /** * Get the implementing enumerated constant for this stored procedure object. * * @return stored procedure enumerated constant */ Enum getEnum(); //NOSONAR } /** * This class defines a package of database objects associated with a query. These include:
    *
  • {@link Connection} object
  • *
  • {@link PreparedStatement} object
  • *
  • {@link ResultSet} object
*/ public static class ResultPackage implements AutoCloseable { private Connection connection; private PreparedStatement statement; private ResultSet resultSet; /** * Constructor for a result package object * * @param connection {@link Connection} object * @param statement {@link PreparedStatement} object * @param resultSet {@link ResultSet} object */ private ResultPackage(Connection connection, PreparedStatement statement, ResultSet resultSet) { this.connection = connection; this.statement = statement; this.resultSet = resultSet; } public Connection getConnection() { return connection; } public PreparedStatement getStatement() { return statement; } public CallableStatement getCallable() { if (statement instanceof CallableStatement) { return (CallableStatement) statement; } throw new UnsupportedOperationException("The statement of this package is not a CallableStatement"); } /** * Get the result set object of this package. * * @return {@link ResultSet} object */ public ResultSet getResultSet() { if (resultSet != null) return resultSet; throw new IllegalStateException("The result set in this package has been closed"); } @Override public void close() { if (resultSet != null) { try { resultSet.close(); resultSet = null; } catch (SQLException e) { } } if (statement != null) { try { statement.close(); statement = null; } catch (SQLException e) { } } if (connection != null) { try { connection.commit(); connection.close(); connection = null; } catch (SQLException e) { } } } } }




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