refactor: completely rewrite SqlTemplate with intelligent SQL parsing and batching

templates/flamingock-sql-template/build.gradle.kts

@@ -1,5 +1,10 @@
 dependencies {
     implementation(project(":core:flamingock-core-commons"))
+
+    testAnnotationProcessor(project(":core:flamingock-processor"))
+    testImplementation(project(":community:flamingock-auditstore-sql"))
+    testImplementation("com.zaxxer:HikariCP:4.0.3")
+    testImplementation("com.h2database:h2:2.1.214")
 }
 
 description = "SQL change templates for declarative database schema and data changes"
@@ -8,4 +13,12 @@ java {
     toolchain {
         languageVersion.set(JavaLanguageVersion.of(8))
     }
-}
+}
+tasks.withType<JavaCompile>().configureEach {
+    if (name.contains("Test", ignoreCase = true)) {
+        options.compilerArgs.addAll(listOf(
+            "-Asources=${projectDir}/src/test/java",
+            "-Aresources=${projectDir}/src/test/resources"
+        ))
+    }
+}

templates/flamingock-sql-template/src/main/java/io/flamingock/template/sql/SqlTemplate.java

@@ -18,31 +18,69 @@
 import io.flamingock.api.annotations.Apply;
 import io.flamingock.api.annotations.Rollback;
 import io.flamingock.api.template.AbstractChangeTemplate;
+import io.flamingock.internal.util.log.FlamingockLoggerFactory;
+import io.flamingock.template.sql.util.SqlStatementParser;
 
 import java.sql.Connection;
 import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.slf4j.Logger;
 
 public class SqlTemplate extends AbstractChangeTemplate<Void, String, String> {
 
+    private final Logger logger = FlamingockLoggerFactory.getLogger(SqlTemplate.class);
+
     public SqlTemplate() {
         super();
     }
 
     @Apply
-    public void apply(Connection connection) {
+    public void apply(Connection connection) throws SQLException {
         execute(connection, applyPayload);
     }
 
     @Rollback
-    public void rollback(Connection connection) {
+    public void rollback(Connection connection) throws SQLException {
         execute(connection, rollbackPayload);
     }
 
-    private static void execute(Connection connection, String sql) {
-        try {
-            connection.createStatement().executeUpdate(sql);
-        } catch (SQLException e) {
-            throw new RuntimeException(e);
+    private void execute(Connection connection, String sql) throws SQLException {
+        if (connection == null) {
+            throw new IllegalArgumentException("connection is null");
+        }
+        if (connection.isClosed()) {
+            throw new IllegalArgumentException("connection is closed");
+        }
+
+        if (sql == null || sql.trim().isEmpty()) {
+            throw new IllegalArgumentException("SQL payload is null or empty");
+        }
+
+        List<String> statements = SqlStatementParser.splitStatements(sql);
+
+        // Group statements by command type for intelligent batching
+        Map<String, List<String>> groupedStatements = new HashMap<>();
+        for (String stmt : statements) {
+            String trimmed = stmt.trim();
+            if (trimmed.isEmpty()) continue;
+            String command = SqlStatementParser.getCommand(trimmed);
+            groupedStatements.computeIfAbsent(command, k -> new ArrayList<>()).add(trimmed);
+        }
+
+        // Execute each group
+        for (Map.Entry<String, List<String>> entry : groupedStatements.entrySet()) {
+            List<String> group = entry.getValue();
+            if (group.size() == 1) {
+                // Single statement, execute individually
+                SqlStatementParser.executeSingle(connection, group.get(0));
+            } else {
+                // Multiple statements of same type, batch them
+                SqlStatementParser.executeMany(connection, group);
+            }
         }
     }
 }

templates/flamingock-sql-template/src/main/java/io/flamingock/template/sql/util/SqlStatementParser.java

@@ -0,0 +1,138 @@
+/*
+ * Copyright 2023 Flamingock (https://www.flamingock.io)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.flamingock.template.sql.util;
+
+import io.flamingock.internal.util.log.FlamingockLoggerFactory;
+
+import java.sql.BatchUpdateException;
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.slf4j.Logger;
+
+public class SqlStatementParser {
+
+    private static final Logger logger = FlamingockLoggerFactory.getLogger(SqlStatementParser.class);
+
+    public static List<String> splitStatements(String sql) {
+        List<String> statements = new ArrayList<>();
+        StringBuilder currentStmt = new StringBuilder();
+        boolean inString = false;
+        boolean inComment = false;
+        boolean inLineComment = false;
+        char stringChar = '"';
+
+        for (int i = 0; i < sql.length(); i++) {
+            char c = sql.charAt(i);
+            char next = (i + 1 < sql.length()) ? sql.charAt(i + 1) : '\0';
+
+            if (!inComment && !inLineComment && !inString && c == '/' && next == '*') {
+                inComment = true;
+                i++; // skip next char
+            } else if (inComment && c == '*' && next == '/') {
+                inComment = false;
+                i++; // skip next char
+            } else if (!inComment && !inString && c == '-' && next == '-') {
+                inLineComment = true;
+                i++; // skip next char
+            } else if (inLineComment && c == '\n') {
+                inLineComment = false;
+            } else if (!inComment && !inLineComment && !inString && (c == '"' || c == '\'')) {
+                inString = true;
+                stringChar = c;
+                currentStmt.append(c);
+            } else if (inString && c == stringChar) {
+                // Check for escaped quote
+                if (i > 0 && sql.charAt(i - 1) == '\\') {
+                    currentStmt.append(c);
+                } else {
+                    inString = false;
+                    currentStmt.append(c);
+                }
+            } else if (!inComment && !inLineComment && !inString && c == ';') {
+                statements.add(normalizeSpaces(currentStmt.toString().trim()));
+                currentStmt.setLength(0);
+            } else if (!inComment && !inLineComment) {
+                currentStmt.append(c);
+            }
+            // Skip comments entirely
+        }
+        if (currentStmt.length() > 0) {
+            statements.add(normalizeSpaces(currentStmt.toString().trim()));
+        }
+        return statements.stream().filter(s -> !s.trim().isEmpty()).collect(java.util.stream.Collectors.toList());
+    }
+
+    public static String getCommand(String sql) {
+        String trimmed = sql.trim();
+        if (trimmed.isEmpty()) {
+            return "UNKNOWN";
+        }
+        String[] parts = trimmed.split("\\s+");
+        return parts.length > 0 ? parts[0].toUpperCase() : "UNKNOWN";
+    }
+
+    public static void executeSingle(Connection connection, String stmtSql) {
+        try (Statement stmt = connection.createStatement()) {
+            stmt.execute(stmtSql);
+        } catch (SQLException e) {
+            String errorMsg = "SQL execution failed: " + stmtSql;
+            logger.error(errorMsg, e);
+            throw new RuntimeException(errorMsg, e);
+        }
+    }
+
+    public static void executeMany(Connection connection, List<String> statements) {
+        try (Statement stmt = connection.createStatement()) {
+            for (String stmtSql : statements) {
+                stmt.addBatch(stmtSql);
+            }
+            stmt.executeBatch();
+        } catch (BatchUpdateException e) {
+            // BatchUpdateException provides updateCounts with failed index
+            int[] updateCounts = e.getUpdateCounts();
+            int failedIndex = -1;
+            for (int i = 0; i < updateCounts.length; i++) {
+                if (updateCounts[i] == Statement.EXECUTE_FAILED) {
+                    failedIndex = i;
+                    break;
+                }
+            }
+            String failedStmt = failedIndex >= 0 ? statements.get(failedIndex) : "unknown";
+            String errorMsg = String.format("Batch execution failed at statement %d: %s", failedIndex + 1, failedStmt);
+            logger.error(errorMsg, e);
+            throw new RuntimeException(errorMsg, e);
+        } catch (SQLException e) {
+            String errorMsg = "Batch execution failed: " + e.getMessage();
+            logger.error(errorMsg, e);
+            throw new RuntimeException(errorMsg, e);
+        }
+    }
+
+    private static String normalizeSpaces(String sql) {
+        if (sql == null) {
+            return null;
+        }
+        // Replace newlines and tabs with spaces
+        String normalized = sql.replaceAll("[\\r\\n\\t]", " ");
+        // Replace multiple spaces with single space
+        normalized = normalized.replaceAll("\\s+", " ");
+        return normalized.trim();
+    }
+}