Polishing.

Changed default behaviour to an empty name for embedded entities. This allows to use embedded entities for column tuples without special prefix. Original pull request #1149

Author: schauder

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/core/PersistentPropertyPathExtensionUnitTests.java

@@ -127,7 +127,7 @@ void getTableAlias() {
 softly.assertThat(extPath("secondList.third.value").getTableAlias()).isEqualTo(quoted("secondList_third"));
 softly.assertThat(extPath("secondList").getTableAlias()).isEqualTo(quoted("secondList"));
 softly.assertThat(extPath("second2.third").getTableAlias()).isEqualTo(quoted("secthird"));
-softly.assertThat(extPath("second3.third").getTableAlias()).isEqualTo(quoted("second3third"));
+softly.assertThat(extPath("second3.third").getTableAlias()).isEqualTo(quoted("third"));
 });
 }
 

spring-data-relational/src/main/java/org/springframework/data/relational/core/mapping/PersistentPropertyPathExtension.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.data.relational.core.mapping;
 
+import java.util.Objects;
+
 import org.springframework.data.mapping.PersistentProperty;
 import org.springframework.data.mapping.PersistentPropertyPath;
 import org.springframework.data.mapping.context.MappingContext;
@@ -23,8 +25,7 @@
 import org.springframework.data.util.Lazy;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
-
-import java.util.Objects;
+import org.springframework.util.StringUtils;
 
 /**
  * A wrapper around a {@link org.springframework.data.mapping.PersistentPropertyPath} for making common operations
@@ -385,28 +386,34 @@ private PersistentPropertyPathExtension getTableOwningAncestor() {
 return isEntity() && !isEmbedded() ? this : getParentPath().getTableOwningAncestor();
 }
 
+@Nullable
 private SqlIdentifier assembleTableAlias() {
 
 Assert.state(path != null, "Path is null");
 
 RelationalPersistentProperty leafProperty = path.getRequiredLeafProperty();
 String prefix;
-if (isEmbedded() && (leafProperty.getEmbeddedPrefix() == null || !leafProperty.getEmbeddedPrefix().isEmpty())) {
+if (isEmbedded()) {
 prefix = leafProperty.getEmbeddedPrefix();
+
 } else {
 prefix = leafProperty.getName();
 }
 
 if (path.getLength() == 1) {
 Assert.notNull(prefix, "Prefix mus not be null.");
-return SqlIdentifier.quoted(prefix);
+return StringUtils.hasText(prefix) ? SqlIdentifier.quoted(prefix) : null;
 }
 
 PersistentPropertyPathExtension parentPath = getParentPath();
 SqlIdentifier sqlIdentifier = parentPath.assembleTableAlias();
 
-return parentPath.isEmbedded() ? sqlIdentifier.transform(name -> name.concat(prefix))
-: sqlIdentifier.transform(name -> name + "_" + prefix);
+if (sqlIdentifier != null) {
+
+return parentPath.isEmbedded() ? sqlIdentifier.transform(name -> name.concat(prefix))
+: sqlIdentifier.transform(name -> name + "_" + prefix);
+}
+return SqlIdentifier.quoted(prefix);
 
 }
 
@@ -444,11 +451,12 @@ private SqlIdentifier prefixWithTableAlias(SqlIdentifier columnName) {
 @Override
 public boolean equals(Object o) {
 
-if (this == o) return true;
-if (o == null || getClass() != o.getClass()) return false;
+if (this == o)
+return true;
+if (o == null || getClass() != o.getClass())
+return false;
 PersistentPropertyPathExtension that = (PersistentPropertyPathExtension) o;
-return entity.equals(that.entity) &&
-Objects.equals(path, that.path);
+return entity.equals(that.entity) && Objects.equals(path, that.path);
 }
 
 @Override