Add STI Discrimination on Reference Associations (#2041)

* Update SqlTreeNodeBean#appendFromBaseTable to add
discriminator values to the join
* Update tests to reflect new generated SQL

src/main/java/io/ebeaninternal/server/query/SqlTreeNodeBean.java

@@ -667,6 +667,9 @@ class SqlTreeNodeBean implements SqlTreeNode {
    */
   SqlJoinType appendFromBaseTable(DbSqlContext ctx, SqlJoinType joinType) {
     SqlJoinType sqlJoinType = appendFromAsJoin(ctx, joinType);
+    if (inheritInfo != null) {
+       appendJoinDiscriminator(ctx);
+    }
     if (desc.isSoftDelete() && temporalMode != SpiQuery.TemporalMode.SOFT_DELETED) {
       ctx.append("and ").append(desc.getSoftDeletePredicate(ctx.getTableAlias(prefix))).append(" ");
     }
@@ -695,6 +698,12 @@ class SqlTreeNodeBean implements SqlTreeNode {
     return nodeBeanProp.addJoin(joinType, prefix, ctx);
   }
 
+  void appendJoinDiscriminator(DbSqlContext ctx) {
+    if (inheritInfo.getWhere() == null) return;
+    String alias = ctx.getTableAlias(prefix);
+    ctx.append(" and ").append(alias).append(".").append(inheritInfo.getWhere());
+  }
+
   /**
    * Summary description.
    */

src/test/java/org/tests/inheritance/TestInheritanceJoins.java

@@ -1,8 +1,6 @@
 package org.tests.inheritance;
 
-import io.ebean.BaseTestCase;
-import io.ebean.Ebean;
-import io.ebean.EbeanServer;
+import io.ebean.*;
 import org.tests.inheritance.model.CalculationResult;
 import org.tests.inheritance.model.Configurations;
 import org.tests.inheritance.model.GroupConfiguration;
@@ -10,6 +8,7 @@ import org.tests.inheritance.model.ProductConfiguration;
 import org.junit.Assert;
 import org.junit.Test;
 
+import java.util.Collections;
 import java.util.List;
 
 public class TestInheritanceJoins extends BaseTestCase {
@@ -86,7 +85,7 @@ public class TestInheritanceJoins extends BaseTestCase {
 
 
     final GroupConfiguration gc = new GroupConfiguration("GC1");
-    configurations.add(gc);
+    configurations.addGroupConfiguration(gc);
 
 
     server.save(gc);
@@ -112,4 +111,25 @@ public class TestInheritanceJoins extends BaseTestCase {
     Assert.assertNotNull(configurationsQueried);
   }
 
+  @Test
+  public void testMultipleAssocManyWithSameInheritanceBase() {
+    Database database = DB.getDefault();
+
+    Configurations configurations = new Configurations();
+    database.save(configurations);
+
+    GroupConfiguration gc = new GroupConfiguration();
+    gc.setConfigurations(configurations);
+    database.save(gc);
+
+    ProductConfiguration pc = new ProductConfiguration();
+    pc.setConfigurations(configurations);
+    database.save(pc);
+
+    Configurations configurationsQueried = database.find(Configurations.class).fetch("groupConfigurations").fetch("productConfigurations").where().idEq(configurations.getId()).findOne();
+
+    Assert.assertEquals(Collections.singletonList(gc), configurationsQueried.getGroupConfigurations());
+    Assert.assertEquals(Collections.singletonList(pc), configurationsQueried.getProductConfigurations());
+  }
+
 }

src/test/java/org/tests/inheritance/bothsides/TestInheritanceBothSides.java

@@ -39,7 +39,7 @@ public class TestInheritanceBothSides extends BaseTestCase {
     final Query<SourceA> query = DB.find(SourceA.class).fetch("target", "name").order("pos");
     query.findList();
 
-    assertThat(sqlOf(query)).contains("select t0.dtype, t0.id, t0.name, t0.pos, t1.dtype, t1.id, t1.name from source_base t0 left join target_base t1 on t1.id = t0.target_id  where t0.dtype = 'SourceA' order by t0.pos");
+    assertThat(sqlOf(query)).contains("select t0.dtype, t0.id, t0.name, t0.pos, t1.dtype, t1.id, t1.name from source_base t0 left join target_base t1 on t1.id = t0.target_id  and t1.dtype = 'Target1' where t0.dtype = 'SourceA' order by t0.pos");
   }
 
   @Test
@@ -89,7 +89,7 @@ public class TestInheritanceBothSides extends BaseTestCase {
 
     final List<String> sql = LoggedSqlCollector.stop();
     assertThat(sql).hasSize(1);
-    assertSql(sql.get(0)).contains("select t0.dtype, t0.id, t0.name, t0.pos, t1.dtype, t1.id, t1.name from source_base t0 left join target_base t1 on t1.id = t0.target_id  where t0.dtype = 'SourceA' order by t0.pos");
+    assertSql(sql.get(0)).contains("select t0.dtype, t0.id, t0.name, t0.pos, t1.dtype, t1.id, t1.name from source_base t0 left join target_base t1 on t1.id = t0.target_id  and t1.dtype = 'Target1' where t0.dtype = 'SourceA' order by t0.pos");
   }
 
   /**

src/test/java/org/tests/inheritance/model/Configurations.java

@@ -17,12 +17,13 @@ public class Configurations {
   @OneToMany
   private List<GroupConfiguration> groupConfigurations;
 
+  @OneToMany
+  private List<ProductConfiguration> productConfigurations;
 
   public Integer getId() {
     return id;
   }
 
-
   public void setId(Integer id) {
     this.id = id;
   }
@@ -39,13 +40,25 @@ public class Configurations {
     return groupConfigurations;
   }
 
-
   public void setGroupConfigurations(List<GroupConfiguration> groupConfigurations) {
     this.groupConfigurations = groupConfigurations;
   }
 
-  public void add(GroupConfiguration groupConfiguration) {
+  public void addGroupConfiguration(GroupConfiguration groupConfiguration) {
     groupConfiguration.setConfigurations(this);
     groupConfigurations.add(groupConfiguration);
   }
+
+  public List<ProductConfiguration> getProductConfigurations() {
+    return productConfigurations;
+  }
+
+  public void setProductConfigurations(List<ProductConfiguration> productConfigurations) {
+    this.productConfigurations = productConfigurations;
+  }
+
+  public void addProductConfiguration(ProductConfiguration productConfiguration) {
+    productConfiguration.setConfigurations(this);
+    productConfigurations.add(productConfiguration);
+  }
 }

src/test/java/org/tests/model/inheritmany/TestMediaInheritanceJoinToMany.java

@@ -29,7 +29,7 @@ public class TestMediaInheritanceJoinToMany extends BaseTestCase {
     Assert.assertNotNull(profile);
 
     String generatedSql = query.getGeneratedSql();
-    assertSql(generatedSql).contains("select t0.id, t0.name, t1.type, t1.id, t1.url, t1.note from mprofile t0 left join mmedia t1 on t1.id = t0.picture_id  where t0.name = ?");
+    assertSql(generatedSql).contains("select t0.id, t0.name, t1.type, t1.id, t1.url, t1.note from mprofile t0 left join mmedia t1 on t1.id = t0.picture_id  and t1.type = 'Picture' where t0.name = ?");
     assertSql(generatedSql).contains("where t0.name = ?");
   }