refactor: replace individual variables with ConnectionProperty

Replace individual variables in ConnectionOptions and ConnectionImpl with
references to ConnectionProperties. This reduces the amount of code bloat,
especially in ConnectionOptions, as all connection property parsing is
now handled by the ConnectionState class in a generic way.

This setup also reduces the amount of code that is needed to add a new
connection property, as there is only one source of truth: the list of
properties in the ConnectionProperties class.

Following steps that will reduce the amount of code bloat further are:
1. Replace all the regular expressions for SET and SHOW statements with
   a simple token-based parser.
2. Cleaning up ConnectionOptions further by removing the duplicate list
   of ConnectionProperties there. These can be removed once the JDBC
   driver has been updated to use the new list of properties.

Author: olavloite

google-cloud-spanner/src/main/java/com/google/cloud/spanner/connection/ClientSideStatementValueConverters.java

@@ -16,6 +16,11 @@
 
 package com.google.cloud.spanner.connection;
 
+import static com.google.cloud.spanner.connection.ReadOnlyStalenessUtil.parseTimeUnit;
+import static com.google.cloud.spanner.connection.ReadOnlyStalenessUtil.toChronoUnit;
+
+import com.google.api.gax.core.CredentialsProvider;
+import com.google.cloud.spanner.Dialect;
 import com.google.cloud.spanner.ErrorCode;
 import com.google.cloud.spanner.Options.RpcPriority;
 import com.google.cloud.spanner.SpannerException;
@@ -27,16 +32,17 @@
 import com.google.common.base.Function;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
-import com.google.protobuf.Duration;
-import com.google.protobuf.util.Durations;
 import com.google.spanner.v1.DirectedReadOptions;
 import com.google.spanner.v1.RequestOptions.Priority;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.time.Duration;
+import java.time.temporal.ChronoUnit;
 import java.util.Base64;
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.Locale;
 import java.util.Map;
-import java.util.concurrent.TimeUnit;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -172,8 +178,11 @@ public Integer convert(String value) {
     }
   }
 
-  /** Converter from string to {@link Duration}. */
+  /** Converter from string to protobuf {@link Duration}. */
   static class DurationConverter implements ClientSideStatementValueConverter<Duration> {
+    static final DurationConverter INSTANCE =
+        new DurationConverter("('(\\d{1,19})(s|ms|us|ns)'|(^\\d{1,19})|NULL)");
+
     private final Pattern allowedValues;
 
     public DurationConverter(String allowedValues) {
@@ -193,13 +202,16 @@ public Duration convert(String value) {
       Matcher matcher = allowedValues.matcher(value);
       if (matcher.find()) {
         if (matcher.group(0).equalsIgnoreCase("null")) {
-          return Durations.fromNanos(0L);
+          return Duration.ofMillis(0L);
         } else {
-          Duration duration =
-              ReadOnlyStalenessUtil.createDuration(
-                  Long.parseLong(matcher.group(1)),
-                  ReadOnlyStalenessUtil.parseTimeUnit(matcher.group(2)));
-          if (duration.getSeconds() == 0L && duration.getNanos() == 0) {
+          Duration duration;
+          if (matcher.group(3) != null) {
+            duration = Duration.ofMillis(Long.parseLong(matcher.group(3)));
+          } else {
+            ChronoUnit unit = toChronoUnit(parseTimeUnit(matcher.group(2)));
+            duration = Duration.of(Long.parseLong(matcher.group(1)), unit);
+          }
+          if (duration.isZero()) {
             return null;
           }
           return duration;
@@ -231,18 +243,14 @@ public Duration convert(String value) {
       if (matcher.find()) {
         Duration duration;
         if (matcher.group(0).equalsIgnoreCase("default")) {
-          return Durations.fromNanos(0L);
+          return Duration.ofMillis(0L);
         } else if (matcher.group(2) == null) {
-          duration =
-              ReadOnlyStalenessUtil.createDuration(
-                  Long.parseLong(matcher.group(0)), TimeUnit.MILLISECONDS);
+          duration = Duration.ofMillis(Long.parseLong(matcher.group(0)));
         } else {
-          duration =
-              ReadOnlyStalenessUtil.createDuration(
-                  Long.parseLong(matcher.group(1)),
-                  ReadOnlyStalenessUtil.parseTimeUnit(matcher.group(2)));
+          ChronoUnit unit = toChronoUnit(parseTimeUnit(matcher.group(2)));
+          duration = Duration.of(Long.parseLong(matcher.group(1)), unit);
         }
-        if (duration.getSeconds() == 0L && duration.getNanos() == 0) {
+        if (duration.isZero()) {
           return null;
         }
         return duration;
@@ -254,6 +262,10 @@ public Duration convert(String value) {
   /** Converter from string to possible values for read only staleness ({@link TimestampBound}). */
   static class ReadOnlyStalenessConverter
       implements ClientSideStatementValueConverter<TimestampBound> {
+    static final ReadOnlyStalenessConverter INSTANCE =
+        new ReadOnlyStalenessConverter(
+            "'((STRONG)|(MIN_READ_TIMESTAMP)[\\t ]+((\\d{4})-(\\d{2})-(\\d{2})([Tt](\\d{2}):(\\d{2}):(\\d{2})(\\.\\d{1,9})?)([Zz]|([+-])(\\d{2}):(\\d{2})))|(READ_TIMESTAMP)[\\t ]+((\\d{4})-(\\d{2})-(\\d{2})([Tt](\\d{2}):(\\d{2}):(\\d{2})(\\.\\d{1,9})?)([Zz]|([+-])(\\d{2}):(\\d{2})))|(MAX_STALENESS)[\\t ]+((\\d{1,19})(s|ms|us|ns))|(EXACT_STALENESS)[\\t ]+((\\d{1,19})(s|ms|us|ns)))'");
+
     private final Pattern allowedValues;
     private final CaseInsensitiveEnumMap<Mode> values = new CaseInsensitiveEnumMap<>(Mode.class);
 
@@ -297,7 +309,7 @@ public TimestampBound convert(String value) {
             try {
               return TimestampBound.ofExactStaleness(
                   Long.parseLong(matcher.group(groupIndex + 2)),
-                  ReadOnlyStalenessUtil.parseTimeUnit(matcher.group(groupIndex + 3)));
+                  parseTimeUnit(matcher.group(groupIndex + 3)));
             } catch (IllegalArgumentException e) {
               throw SpannerExceptionFactory.newSpannerException(
                   ErrorCode.INVALID_ARGUMENT, e.getMessage());
@@ -306,7 +318,7 @@ public TimestampBound convert(String value) {
             try {
               return TimestampBound.ofMaxStaleness(
                   Long.parseLong(matcher.group(groupIndex + 2)),
-                  ReadOnlyStalenessUtil.parseTimeUnit(matcher.group(groupIndex + 3)));
+                  parseTimeUnit(matcher.group(groupIndex + 3)));
             } catch (IllegalArgumentException e) {
               throw SpannerExceptionFactory.newSpannerException(
                   ErrorCode.INVALID_ARGUMENT, e.getMessage());
@@ -539,7 +551,12 @@ public PgTransactionMode convert(String value) {
     }
   }
 
-  /** Converter for converting strings to {@link RpcPriority} values. */
+  /**
+   * Converter for converting strings to {@link Priority} values.
+   *
+   * @deprecated Use {@link RpcPriorityEnumConverter} instead.
+   */
+  @Deprecated
   static class RpcPriorityConverter implements ClientSideStatementValueConverter<Priority> {
     private final CaseInsensitiveEnumMap<Priority> values =
         new CaseInsensitiveEnumMap<>(Priority.class);
@@ -569,12 +586,43 @@ public Priority convert(String value) {
     }
   }
 
+  /** Converter for converting strings to {@link RpcPriority} values. */
+  static class RpcPriorityEnumConverter implements ClientSideStatementValueConverter<RpcPriority> {
+    static final RpcPriorityEnumConverter INSTANCE = new RpcPriorityEnumConverter();
+
+    private final CaseInsensitiveEnumMap<RpcPriority> values =
+        new CaseInsensitiveEnumMap<>(RpcPriority.class);
+
+    private RpcPriorityEnumConverter() {}
+
+    /** Constructor needed for reflection. */
+    public RpcPriorityEnumConverter(String allowedValues) {}
+
+    @Override
+    public Class<RpcPriority> getParameterClass() {
+      return RpcPriority.class;
+    }
+
+    @Override
+    public RpcPriority convert(String value) {
+      if ("null".equalsIgnoreCase(value)) {
+        return RpcPriority.UNSPECIFIED;
+      }
+      return values.get(value);
+    }
+  }
+
   /** Converter for converting strings to {@link SavepointSupport} values. */
   static class SavepointSupportConverter
       implements ClientSideStatementValueConverter<SavepointSupport> {
+    static final SavepointSupportConverter INSTANCE = new SavepointSupportConverter();
+
     private final CaseInsensitiveEnumMap<SavepointSupport> values =
         new CaseInsensitiveEnumMap<>(SavepointSupport.class);
 
+    private SavepointSupportConverter() {}
+
+    /** Constructor needed for reflection. */
     public SavepointSupportConverter(String allowedValues) {}
 
     @Override
@@ -588,6 +636,30 @@ public SavepointSupport convert(String value) {
     }
   }
 
+  /** Converter for converting strings to {@link DdlInTransactionMode} values. */
+  static class DdlInTransactionModeConverter
+      implements ClientSideStatementValueConverter<DdlInTransactionMode> {
+    static final DdlInTransactionModeConverter INSTANCE = new DdlInTransactionModeConverter();
+
+    private final CaseInsensitiveEnumMap<DdlInTransactionMode> values =
+        new CaseInsensitiveEnumMap<>(DdlInTransactionMode.class);
+
+    private DdlInTransactionModeConverter() {}
+
+    /** Constructor needed for reflection. */
+    public DdlInTransactionModeConverter(String allowedValues) {}
+
+    @Override
+    public Class<DdlInTransactionMode> getParameterClass() {
+      return DdlInTransactionMode.class;
+    }
+
+    @Override
+    public DdlInTransactionMode convert(String value) {
+      return values.get(value);
+    }
+  }
+
   static class ExplainCommandConverter implements ClientSideStatementValueConverter<String> {
     @Override
     public Class<String> getParameterClass() {
@@ -648,4 +720,71 @@ public String convert(String filePath) {
       return filePath;
     }
   }
+
+  static class CredentialsProviderConverter
+      implements ClientSideStatementValueConverter<CredentialsProvider> {
+    static final CredentialsProviderConverter INSTANCE = new CredentialsProviderConverter();
+
+    private CredentialsProviderConverter() {}
+
+    @Override
+    public Class<CredentialsProvider> getParameterClass() {
+      return CredentialsProvider.class;
+    }
+
+    @Override
+    public CredentialsProvider convert(String credentialsProviderName) {
+      if (!Strings.isNullOrEmpty(credentialsProviderName)) {
+        try {
+          Class<? extends CredentialsProvider> clazz =
+              (Class<? extends CredentialsProvider>) Class.forName(credentialsProviderName);
+          Constructor<? extends CredentialsProvider> constructor = clazz.getDeclaredConstructor();
+          return constructor.newInstance();
+        } catch (ClassNotFoundException classNotFoundException) {
+          throw SpannerExceptionFactory.newSpannerException(
+              ErrorCode.INVALID_ARGUMENT,
+              "Unknown or invalid CredentialsProvider class name: " + credentialsProviderName,
+              classNotFoundException);
+        } catch (NoSuchMethodException noSuchMethodException) {
+          throw SpannerExceptionFactory.newSpannerException(
+              ErrorCode.INVALID_ARGUMENT,
+              "Credentials provider "
+                  + credentialsProviderName
+                  + " does not have a public no-arg constructor.",
+              noSuchMethodException);
+        } catch (InvocationTargetException
+            | InstantiationException
+            | IllegalAccessException exception) {
+          throw SpannerExceptionFactory.newSpannerException(
+              ErrorCode.INVALID_ARGUMENT,
+              "Failed to create an instance of "
+                  + credentialsProviderName
+                  + ": "
+                  + exception.getMessage(),
+              exception);
+        }
+      }
+      return null;
+    }
+  }
+
+  /** Converter for converting strings to {@link Dialect} values. */
+  static class DialectConverter implements ClientSideStatementValueConverter<Dialect> {
+    static final DialectConverter INSTANCE = new DialectConverter();
+
+    private final CaseInsensitiveEnumMap<Dialect> values =
+        new CaseInsensitiveEnumMap<>(Dialect.class);
+
+    private DialectConverter() {}
+
+    @Override
+    public Class<Dialect> getParameterClass() {
+      return Dialect.class;
+    }
+
+    @Override
+    public Dialect convert(String value) {
+      return values.get(value);
+    }
+  }
 }