Replace @IdClass with @embeddable for composite primary keys

Author: ngbsn

src/main/java/org/ngbsn/generator/ModelGenerator.java

@@ -7,6 +7,7 @@
 import net.sf.jsqlparser.statement.create.table.Index;
 import org.apache.commons.text.CaseUtils;
 import org.ngbsn.model.Column;
+import org.ngbsn.model.EmbeddableClass;
 import org.ngbsn.model.ForeignKeyConstraint;
 import org.ngbsn.model.Table;
 import org.ngbsn.model.annotations.entityAnnotations.EntityAnnotation;
@@ -99,6 +100,12 @@ private static void extractPrimaryKeys(CreateTable parsedTable, Table table) {
         if (columnParamsList != null) {
             if (columnParamsList.size() > 1) {
                 table.setNumOfPrimaryKeyColumns(columnParamsList.size());
+                EmbeddableClass embeddableClass = EmbeddableClass
+                        .builder()
+                        .className(table.getClassName() + "PK")
+                        .fieldName(CaseUtils.toCamelCase(table.getName(), false, '_') + "PK")
+                        .build();
+                table.setEmbeddableClass(embeddableClass);
             }
             List<Column> primaryKeyColumns = table.getColumns().stream().
                     filter(column -> columnParamsList.stream().anyMatch(columnParams -> columnParams.getColumnName().equals(column.getName()))).toList();

src/main/java/org/ngbsn/model/EmbeddableClass.java

@@ -0,0 +1,13 @@
+package org.ngbsn.model;
+
+import lombok.Builder;
+import lombok.Getter;
+import lombok.Setter;
+
+@Builder
+@Setter
+@Getter
+public class EmbeddableClass {
+    private String className;
+    private String fieldName;
+}

src/main/java/org/ngbsn/model/Table.java

@@ -17,5 +17,6 @@ public class Table {
     private List<String> annotations = new ArrayList<>();
     private int numOfPrimaryKeyColumns;
     private List<ForeignKeyConstraint> foreignKeyConstraints = new ArrayList<>();
+    private EmbeddableClass embeddableClass;
 
 }

src/main/resources/templates/entity.ftl

@@ -7,27 +7,40 @@ import ${import};
 <#list table.annotations as annotation>
 ${annotation}
 </#list>
-<#if (table.numOfPrimaryKeyColumns > 1) >
-@IdClass(${table.className}.${table.className}PK.class)
-</#if>
+
 public class ${table.className}{
 <#if (table.numOfPrimaryKeyColumns > 1) >
-    static class ${table.className}PK implements Serializable{
+    @Embeddable
+    static class ${table.embeddableClass.className} implements Serializable{
         <#list table.columns as column>
         <#if column.primaryKey == true>
-            private ${column.type} ${column.fieldName};
+        <#list column.annotations as annotation>
+        ${annotation}
+        </#list>
+        private ${column.type} ${column.fieldName};
         </#if>
         </#list>
     }
-</#if>
 
-<#list table.columns as column>
-<#if column.primaryKey == true>
+    @EmbeddedId
+    private ${table.embeddableClass.className} ${table.embeddableClass.fieldName};
+    <#list table.columns as column>
+    <#if column.primaryKey == false>
+    <#list column.annotations as annotation>
+    ${annotation}
+    </#list>
+    private ${column.type} ${column.fieldName};
+    </#if>
+    </#list>
+<#else>
+    <#list table.columns as column>
+    <#if column.primaryKey == true>
     @Id
-</#if>
-<#list column.annotations as annotation>
+    </#if>
+    <#list column.annotations as annotation>
     ${annotation}
-</#list>
+    </#list>
     private ${column.type} ${column.fieldName};
-</#list>
+    </#list>
+</#if>
 }

src/test/resources/sql/organization.sql

@@ -51,7 +51,7 @@ CREATE TABLE organization.titles (
     from_date   DATE            NOT NULL,
     to_date     DATE,
     FOREIGN KEY (emp_no) REFERENCES organization.employees (emp_no) ON DELETE CASCADE,
-    PRIMARY KEY (emp_no,title, from_date)
+    PRIMARY KEY (title, from_date)
 );