code cleanup and refactor

Author: ngbsn

src/main/java/io/github/ngbsn/generator/AssociationMappingsGenerator.java

@@ -17,6 +17,13 @@
  */
 public class AssociationMappingsGenerator {
 
+
+    private AssociationMappingsGenerator() {
+    }
+
+    /**
+     * Generate both UniDirectional and BiDirectional association mappings for all tables
+     */
     public static void generateMappings() {
         Iterator<Map.Entry<String, Table>> it = tablesMap.entrySet().iterator();
         while (it.hasNext()) {
@@ -44,9 +51,7 @@ public static void generateMappings() {
                     //Case1: There are some fields that are not foreign keys. So separate entity is needed to track Link Table
                     //Case2: All fields are foreign keys. But, the relation exits between 2 or more entities
                     //Add @ManyToOne for each foreignKey and corresponding @OneToMany in referenced Table
-                    foreignKeyConstraintList.forEach(foreignKeyConstraint -> {
-                        addBothSideUniDirectionalMappings(table, foreignKeyConstraint);
-                    });
+                    foreignKeyConstraintList.forEach(foreignKeyConstraint -> addBothSideUniDirectionalMappings(table, foreignKeyConstraint));
                 }
             }
         }

src/main/java/io/github/ngbsn/generator/BiDirectionalMappingsGenerator.java

@@ -3,9 +3,9 @@
 import io.github.ngbsn.model.Column;
 import io.github.ngbsn.model.ForeignKeyConstraint;
 import io.github.ngbsn.model.Table;
-import io.github.ngbsn.model.annotations.fieldAnnotations.JoinColumnAnnotation;
-import io.github.ngbsn.model.annotations.fieldAnnotations.JoinTableAnnotation;
-import io.github.ngbsn.model.annotations.fieldAnnotations.ManyToManyAnnotation;
+import io.github.ngbsn.model.annotations.field.JoinColumnAnnotation;
+import io.github.ngbsn.model.annotations.field.JoinTableAnnotation;
+import io.github.ngbsn.model.annotations.field.ManyToManyAnnotation;
 import io.github.ngbsn.util.Util;
 
 import java.util.HashSet;
@@ -15,6 +15,15 @@
 import static io.github.ngbsn.generator.ModelGenerator.tablesMap;
 
 public class BiDirectionalMappingsGenerator {
+
+    private BiDirectionalMappingsGenerator() {
+    }
+
+    /**
+     * Generate BiDirectional Mappings (many-to-many) for a specific table
+     * @param table The table to be processed
+     * @param foreignKeyConstraintList List of generated foreignKeyConstraintList models
+     */
     static void addBiDirectionalMappings(Table table, List<ForeignKeyConstraint> foreignKeyConstraintList) {
         Table table1 = tablesMap.get(foreignKeyConstraintList.get(0).getReferencedTableName().replaceAll("[\"']", ""));
         Table table2 = tablesMap.get(foreignKeyConstraintList.get(1).getReferencedTableName().replaceAll("[\"']", ""));

src/main/java/io/github/ngbsn/generator/JPACodeGenerator.java

@@ -6,6 +6,7 @@
 import freemarker.template.TemplateException;
 import freemarker.template.TemplateExceptionHandler;
 import io.github.ngbsn.model.Table;
+import lombok.extern.slf4j.Slf4j;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -18,27 +19,50 @@
 
 import static io.github.ngbsn.util.Util.packageNameToFolderStructure;
 
+@Slf4j
 public class JPACodeGenerator {
     private static final Logger logger = LoggerFactory.getLogger(JPACodeGenerator.class);
 
-    public static void main(String[] args) throws TemplateException, IOException {
-        String sqlScript = new BufferedReader(
-                new InputStreamReader(new FileInputStream(args[0]), StandardCharsets.UTF_8))
-                .lines()
-                .collect(Collectors.joining("\n"));
-        generateCode(sqlScript, args[1]);
+    public static void main(final String[] args) throws TemplateException, IOException {
+        try (BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(new FileInputStream(args[0]), StandardCharsets.UTF_8))) {
+            String sqlScript = bufferedReader
+                    .lines()
+                    .collect(Collectors.joining("\n"));
+            generateCode(sqlScript, args[1]);
+        } catch (Exception e) {
+            log.error("Error occurred while running the tool", e);
+        }
     }
 
+    /**
+     *
+     * @param sqlScript The input DDL commands used for generating the models
+     * @param packageName package name for the entities sources to be generated
+     * @throws IOException Thrown if template couldn't be read
+     * @throws TemplateException Thrown if template couldn't be processed
+     */
     public static void generateCode(final String sqlScript, final String packageName) throws IOException, TemplateException {
         logger.info("sql script {}", sqlScript);
         List<Table> tables = generateModels(sqlScript);
         processTemplate(tables, packageName);
     }
 
+    /**
+     * Generate the models needed to generate the sources
+     * @param sqlScript The input DDL commands used for generating the models
+     * @return List of Table models
+     */
     private static List<Table> generateModels(final String sqlScript) {
         return ModelGenerator.parse(sqlScript);
     }
 
+    /**
+     * This method processes the Apache FreeMarker entity template using the generated models
+     * @param tables Generated models
+     * @param packageName package name for the entities sources to be generated
+     * @throws IOException Thrown if template couldn't be read
+     * @throws TemplateException Thrown if template cannot be processed
+     */
     private static void processTemplate(final List<Table> tables, final String packageName) throws IOException, TemplateException {
         /* Create and adjust the configuration singleton */
         Configuration cfg = new Configuration(Configuration.VERSION_2_3_32);

src/main/java/io/github/ngbsn/generator/ModelGenerator.java

@@ -4,10 +4,10 @@
 import io.github.ngbsn.model.EmbeddableClass;
 import io.github.ngbsn.model.ForeignKeyConstraint;
 import io.github.ngbsn.model.Table;
-import io.github.ngbsn.model.annotations.entityAnnotations.EntityAnnotation;
-import io.github.ngbsn.model.annotations.entityAnnotations.TableAnnotation;
-import io.github.ngbsn.model.annotations.fieldAnnotations.ColumnAnnotation;
-import io.github.ngbsn.model.annotations.fieldAnnotations.NotNullAnnotation;
+import io.github.ngbsn.model.annotations.entity.EntityAnnotation;
+import io.github.ngbsn.model.annotations.entity.TableAnnotation;
+import io.github.ngbsn.model.annotations.field.ColumnAnnotation;
+import io.github.ngbsn.model.annotations.field.NotNullAnnotation;
 import io.github.ngbsn.util.SQLToJavaMapping;
 import io.github.ngbsn.util.Util;
 import net.sf.jsqlparser.parser.CCJSqlParserUtil;
@@ -27,9 +27,20 @@
  * It will also extract all the columns from the script and add to the Table model
  */
 public class ModelGenerator {
+
+    public static final String REGEX_ALL_QUOTES = "[\"']";
+
+    private ModelGenerator() {
+    }
+
     private static final Logger logger = LoggerFactory.getLogger(ModelGenerator.class);
     protected static Map<String, Table> tablesMap = new HashMap<>();
 
+    /**
+     * Parse the DDL statements using JSQL parser
+     * @param sqlScript The input DDL commands used for generating the models
+     * @return List of Tables models
+     */
     public static List<Table> parse(final String sqlScript) {
         try {
             Statements statements = CCJSqlParserUtil.parseStatements(sqlScript);
@@ -40,7 +51,7 @@ public static List<Table> parse(final String sqlScript) {
         } catch (Exception e) {
             logger.error("Error occurred", e);
         }
-        return null;
+        return new ArrayList<>();
     }
 
     /**
@@ -51,16 +62,15 @@ public static void clearTablesMap() {
     }
 
     /**
-     * Iterate over all the Create Table statements and prepare the list of Table Model
-     *
-     * @param statements set of statements
+     * Iterate over all the JSQL Create Table  statements and prepare the list of Table Model
+     * @param statements Set of JSQL statements
      */
-    private static void processCreateTableStatements(Statements statements) {
+    private static void processCreateTableStatements(final Statements statements) {
         statements.getStatements().forEach(statement -> {
             //Iterating over all Tables
             if (statement instanceof CreateTable parsedTable) {
                 Table table = new Table();
-                table.setTableName(parsedTable.getTable().getName().replaceAll("[\"']", ""));
+                table.setTableName(parsedTable.getTable().getName().replaceAll(REGEX_ALL_QUOTES, ""));
                 tablesMap.put(table.getTableName(), table);
                 table.setClassName(Util.convertSnakeCaseToCamelCase(table.getTableName(), true));
 
@@ -82,26 +92,25 @@ private static void processCreateTableStatements(Statements statements) {
                 extractPrimaryKeys(optionalIndex.orElse(null), table);
 
                 //extract foreign keys
-                List<Index> foreignKeyIndexes = parsedTable.getIndexes().stream().filter(index -> index instanceof ForeignKeyIndex).toList();
+                List<Index> foreignKeyIndexes = parsedTable.getIndexes().stream().filter(ForeignKeyIndex.class::isInstance).toList();
                 extractForeignKeys(foreignKeyIndexes, table);
             }
         });
     }
 
     /**
-     * Iterate over all the Alter Table statements and prepare the list of Table Model
-     *
-     * @param statements set of statements
+     * Iterate over all the JSQL Alter Table statements and prepare the list of Table Model
+     * @param statements Set of JSQL statements
      */
-    private static void processAlterTableStatements(Statements statements) {
+    private static void processAlterTableStatements(final Statements statements) {
         statements.getStatements().forEach(statement -> {
             //Iterating over all Tables
             // Look for primary and foreign keys in ALTER TABLE constraints
             if (statement instanceof Alter alterTable) {
-                Table table = tablesMap.get(alterTable.getTable().getName().replaceAll("[\"']", ""));
+                Table table = tablesMap.get(alterTable.getTable().getName().replaceAll(REGEX_ALL_QUOTES, ""));
                 List<Index> foreignKeyIndexes = new ArrayList<>();
                 alterTable.getAlterExpressions().forEach(alterExpression -> {
-                    if (alterExpression.getIndex() instanceof ForeignKeyIndex foreignKeyIndex) {
+                    if (alterExpression.getIndex() instanceof ForeignKeyIndex) {
                         //case: ALTER TABLE FOREIGN KEY
                         foreignKeyIndexes.add(alterExpression.getIndex());
                     } else if (alterExpression.getIndex().getType().equals("PRIMARY KEY")) {
@@ -116,39 +125,39 @@ private static void processAlterTableStatements(Statements statements) {
 
 
     /**
-     * Looking for all foreign keys in this table and adding it to our model
-     *
-     * @param foreignKeyIndexes List of foreign key indexes
+     * Looking for all JSQL foreign keys in this table and adding it to our model
+     * @param foreignKeyIndexes List of JSQL foreign key indexes
      * @param table             Table model
      */
-    private static void extractForeignKeys(List<Index> foreignKeyIndexes, Table table) {
+    private static void extractForeignKeys(final List<Index> foreignKeyIndexes, final Table table) {
         if (!foreignKeyIndexes.isEmpty()) {
             foreignKeyIndexes.forEach(index -> {
                 if (index instanceof ForeignKeyIndex foreignKeyIndex) {
                     ForeignKeyConstraint foreignKeyConstraint = new ForeignKeyConstraint();
                     foreignKeyConstraint.setColumns(foreignKeyIndex.getColumnsNames()
-                            .stream().map(s -> s.replaceAll("[\"']", "")).collect(Collectors.toList()));
+                            .stream().map(s -> s.replaceAll(REGEX_ALL_QUOTES, "")).toList());
                     foreignKeyConstraint.setReferencedColumns(foreignKeyIndex.getReferencedColumnNames()
-                            .stream().map(s -> s.replaceAll("[\"']", "")).collect(Collectors.toList()));
+                            .stream().map(s -> s.replaceAll(REGEX_ALL_QUOTES, "")).toList());
                     foreignKeyConstraint.setReferencedTableName(foreignKeyIndex.getTable().getName()
-                            .replaceAll("[\"']", ""));
+                            .replaceAll(REGEX_ALL_QUOTES, ""));
                     table.getForeignKeyConstraints().add(foreignKeyConstraint);
+
                 }
             });
         }
     }
 
     /**
-     * Extracting primary key information from the parsed data and setting them into the Table model
+     * Extracting primary key information from the JSQL parsed data and setting them into the Table model
      *
-     * @param primaryKeyIndex primaryKeyIndex
+     * @param primaryKeyIndex JSQL primaryKeyIndex
      * @param table           Table model
      */
-    private static void extractPrimaryKeys(Index primaryKeyIndex, Table table) {
+    private static void extractPrimaryKeys(final Index primaryKeyIndex, final Table table) {
         List<Index.ColumnParams> columnParamsList = primaryKeyIndex != null ? primaryKeyIndex.getColumns() : null;
         if (columnParamsList != null) {
             Set<Column> primaryKeyColumns = table.getColumns().stream().
-                    filter(column -> columnParamsList.stream().anyMatch(columnParams -> columnParams.getColumnName().replaceAll("[\"']", "").equals(column.getColumnName()))).collect(Collectors.toSet());
+                    filter(column -> columnParamsList.stream().anyMatch(columnParams -> columnParams.getColumnName().replaceAll(REGEX_ALL_QUOTES, "").equals(column.getColumnName()))).collect(Collectors.toSet());
 
             if (columnParamsList.size() > 1) {
                 table.setNumOfPrimaryKeyColumns(columnParamsList.size());
@@ -170,22 +179,21 @@ private static void extractPrimaryKeys(Index primaryKeyIndex, Table table) {
     }
 
     /**
-     * Generate column models for all the parsed table
-     *
-     * @param parsedTable Parsed table
-     * @param columns     List of generated column models
+     * Generate column models for the JSQL parsed table
+     * @param parsedTable JSQL CreateTable
+     * @param columns     Set of generated column models
      */
-    private static void extractColumns(CreateTable parsedTable, Set<Column> columns) {
+    private static void extractColumns(final CreateTable parsedTable, final Set<Column> columns) {
         parsedTable.getColumnDefinitions().forEach(columnDefinition -> {
             Column column = new Column();
             columns.add(column);
             Set<String> columnAnnotations = new HashSet<>();
             column.setAnnotations(columnAnnotations);
-            column.setColumnName(columnDefinition.getColumnName().replaceAll("[\"']", ""));
+            column.setColumnName(columnDefinition.getColumnName().replaceAll(REGEX_ALL_QUOTES, ""));
             //Adding @Column
             columnAnnotations.add(ColumnAnnotation.builder().columnName(column.getColumnName()).build().toString());
             column.setFieldName(Util.convertSnakeCaseToCamelCase(column.getColumnName(), false));
-            column.setType(SQLToJavaMapping.sqlToJavaMap.get(columnDefinition.getColDataType().getDataType()));
+            column.setType(SQLToJavaMapping.getSqlToJavaMap().get(columnDefinition.getColDataType().getDataType()));
 
             //Check for NOT NULL
             if (columnDefinition.getColumnSpecs() != null) {

src/main/java/io/github/ngbsn/generator/UniDirectionalMappingsGenerator.java

@@ -4,7 +4,7 @@
 import io.github.ngbsn.model.EmbeddableClass;
 import io.github.ngbsn.model.ForeignKeyConstraint;
 import io.github.ngbsn.model.Table;
-import io.github.ngbsn.model.annotations.fieldAnnotations.*;
+import io.github.ngbsn.model.annotations.field.*;
 import io.github.ngbsn.util.Util;
 import org.apache.commons.text.WordUtils;
 
@@ -18,11 +18,13 @@
 
 public class UniDirectionalMappingsGenerator {
 
+    private UniDirectionalMappingsGenerator() {
+    }
+
     /**
-     * This method will handle each foreign key constraint in the table.
-     *
-     * @param table                table
-     * @param foreignKeyConstraint foreignKeyConstraint
+     * Generate UniDirectional Mappings (one-to-many and many-to-one) for a specific table
+     * @param table                Table model
+     * @param foreignKeyConstraint ForeignKeyConstraint model
      */
     static void addBothSideUniDirectionalMappings(Table table, ForeignKeyConstraint foreignKeyConstraint) {
         Table referencedTable = tablesMap.get(foreignKeyConstraint.getReferencedTableName().replaceAll("[\"']", ""));
@@ -64,15 +66,15 @@ private static void handleSingleForeignKey(Table table, ForeignKeyConstraint for
             Column foreignKeyColumn = optionalColumn.get();
             //Check if foreign key is also a primary key, by iterating through the primary key list
             Optional<Column> optionalColumnPrimaryForeign = allPrimaryKeyColumns.stream().filter(column -> column.getColumnName() != null && column.getColumnName().equals(foreignKeyColumn.getColumnName())).findFirst();
-            optionalColumnPrimaryForeign.ifPresentOrElse(column -> {
+            optionalColumnPrimaryForeign.ifPresentOrElse(column ->
                 //Case: Shared Primary key
                 //If foreign key is a primary key, don't remove it from table.
                 //Add a @MapsId annotation to the referenced table field
-                parentTableField.getAnnotations().add(MapsIdAnnotation.builder().fieldName(column.getFieldName()).build().toString());
-            }, () -> {
+                parentTableField.getAnnotations().add(MapsIdAnnotation.builder().fieldName(column.getFieldName()).build().toString())
+            , () ->
                 //If foreign key is not a primary key, then remove it from the table
-                optionalColumn.ifPresent(column -> table.getColumns().remove(column));
-            });
+                optionalColumn.ifPresent(column -> table.getColumns().remove(column))
+            );
         }
         //Add a @JoinColumn annotation for the referenced table field
         parentTableField.getAnnotations().add(JoinColumnAnnotation.builder().name(foreignKeyConstraint.getReferencedColumns().get(0)).referencedColumnName(foreignKeyConstraint.getReferencedColumns().get(0)).build().toString());

src/main/java/io/github/ngbsn/maven/JPACodeGenMojo.java

@@ -2,6 +2,7 @@
 
 import io.github.ngbsn.generator.JPACodeGenerator;
 import lombok.SneakyThrows;
+import lombok.extern.slf4j.Slf4j;
 import org.apache.maven.plugin.AbstractMojo;
 import org.apache.maven.plugin.MojoExecutionException;
 import org.apache.maven.plugin.MojoFailureException;
@@ -17,6 +18,7 @@
 import java.util.stream.Collectors;
 
 @Mojo(name = "parse-schema")
+@Slf4j
 public class JPACodeGenMojo extends AbstractMojo {
     private static final Logger logger = LoggerFactory.getLogger(JPACodeGenMojo.class);
 
@@ -37,10 +39,16 @@ public class JPACodeGenMojo extends AbstractMojo {
     public void execute() throws MojoExecutionException, MojoFailureException {
         logger.info("Executing the goal parse-schema {} {}", sqlFilePath, packageName);
 
-        String sqlScript = new BufferedReader(
-                new InputStreamReader(new FileInputStream(sqlFilePath), StandardCharsets.UTF_8))
-                .lines()
-                .collect(Collectors.joining("\n"));
-        JPACodeGenerator.generateCode(sqlScript, packageName);
+        try (BufferedReader bufferedReader = new BufferedReader(
+                new InputStreamReader(new FileInputStream(sqlFilePath), StandardCharsets.UTF_8))) {
+            String sqlScript = bufferedReader
+                    .lines()
+                    .collect(Collectors.joining("\n"));
+            JPACodeGenerator.generateCode(sqlScript, packageName);
+        } catch (Exception e) {
+            log.error("Error occurred while running the plugin", e);
+        }
+
+
     }
 }

…/entityAnnotations/EntityAnnotation.java …annotations/entity/EntityAnnotation.javasrc/main/java/io/github/ngbsn/model/annotations/entityAnnotations/EntityAnnotation.java renamed to src/main/java/io/github/ngbsn/model/annotations/entity/EntityAnnotation.java src/main/java/io/github/ngbsn/model/annotations/entityAnnotations/EntityAnnotation.java renamed to src/main/java/io/github/ngbsn/model/annotations/entity/EntityAnnotation.java

@@ -1,4 +1,4 @@
-package io.github.ngbsn.model.annotations.entityAnnotations;
+package io.github.ngbsn.model.annotations.entity;
 
 import io.github.ngbsn.model.annotations.Annotation;
 

…s/entityAnnotations/TableAnnotation.java …/annotations/entity/TableAnnotation.javasrc/main/java/io/github/ngbsn/model/annotations/entityAnnotations/TableAnnotation.java renamed to src/main/java/io/github/ngbsn/model/annotations/entity/TableAnnotation.java src/main/java/io/github/ngbsn/model/annotations/entityAnnotations/TableAnnotation.java renamed to src/main/java/io/github/ngbsn/model/annotations/entity/TableAnnotation.java

@@ -1,4 +1,4 @@
-package io.github.ngbsn.model.annotations.entityAnnotations;
+package io.github.ngbsn.model.annotations.entity;
 
 import io.github.ngbsn.model.annotations.Annotation;
 import lombok.Builder;