resolve attributes

Author: slowcoders

hyperquery/src/main/java/org/slowcoders/hyperquery/impl/JoinNode.java

@@ -2,11 +2,12 @@
 
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.TreeMap;
 
 class ViewNode {
     final HashMap<String, String> usedAttributes = new HashMap<>();
 
-    final HashMap<String, JoinNode> joins = new HashMap<>();
+    final TreeMap<String, JoinNode> joins = new TreeMap<>();
 
     protected JoinNode getJoin(String aliasQualifier) {
         return joins.get(aliasQualifier);
@@ -31,9 +32,7 @@ class JoinNode {
 
     final boolean addUsedAttribute(String alias, String expr) {
         for (int i = attrLevel; --i >= 0; ) {
-            if (views.get(i).usedAttributes.containsKey(alias)) {
-                return false;
-            }
+            views.get(i).usedAttributes.remove(alias);
         }
         for (int i = views.size(); --i >= attrLevel; ) {
             if (views.get(i).usedAttributes.containsKey(alias)) {

hyperquery/src/main/java/org/slowcoders/hyperquery/impl/QAttribute.java

@@ -7,14 +7,24 @@
 public class QAttribute {
 
     private final String sql;
+    boolean inProgress = false;
     public QAttribute(String sql) {
         this.sql = sql;
     }
 
     public String getExpression() { return sql; }
 
-    public final String inflateStatement(SqlBuilder generator, String paramName) {
-        return PredicateTranslator.translate(generator, paramName, sql);
+    public synchronized final String inflateStatement(SqlBuilder generator, String paramName) {
+        if (inProgress) {
+            throw new IllegalStateException("Circular attribute reference is found.");
+        }
+        try {
+            inProgress = true;
+            String expr = PredicateTranslator.translate(generator, paramName, sql);
+            return expr;
+        } finally {
+            inProgress = false;
+        }
     }
 
     public static QAttribute of(String statement) {

hyperquery/src/main/java/org/slowcoders/hyperquery/impl/SqlBuilder.java

@@ -94,6 +94,7 @@ String resolveLambda(String path, List<String> callArgs) {
         });
     }
 
+
     public String resolveProperty(String path) {
         return this.resolveQualifiedAlias(path, (model, name) -> {
             QAttribute attr = model.getAttribute(name);
@@ -155,7 +156,7 @@ private void genFrom(StringBuilder sb, StringBuilder sbWith) {
         genJoin(sb, sbWith, currView.joins);
     }
 
-    private void genJoin(StringBuilder sb, StringBuilder sbWith, HashMap<String, JoinNode> joinNodes) {
+    private void genJoin(StringBuilder sb, StringBuilder sbWith, Map<String, JoinNode> joinNodes) {
         for (Map.Entry<String, JoinNode> entry : joinNodes.entrySet()) {
             String alias = entry.getKey();
             JoinNode node = entry.getValue();

sample-app/src/main/java/org/slowcoders/hyperql/sample/hq/bookstore/AuthorDto.java

@@ -28,6 +28,9 @@ public class AuthorDto implements QRecord<Author> {
 
     @QColumn("bookPriceAvr")
     private int bookPriceAvr;
+
+//    @QColumn("attr2")
+//    private int attr2;
 }
 
 

sample-app/src/main/java/org/slowcoders/hyperql/sample/hq/bookstore/model/Author.java

@@ -28,6 +28,14 @@ select sum(price) * @.bookCount from bookstore.book bk where bk.author_id = @.id
             @.bookCount * @.bookPriceAvr
             """);
 
+    static final QAttribute attr1 = Property.formula("""
+            @.attr2 * 30
+            """);
+    static final QAttribute attr2 = Property.formula("""
+            @.attr1 * 30
+            """);
+
+
     @Id
     @Column(name = "id", nullable = false)
     @PKColumn("id")

tutorial+test/tests/unit/hql.spec.js

@@ -4,7 +4,7 @@ import axios from "axios";
 
 describe('Hyper Query operations', () => {
 
-    initSampleDB();
+    // initSampleDB();
 
     const baseUrl = "http://localhost:7007/api/hq/authors"