adds complete joins to select from

src/main/kotlin/unibz.cs.semint.kprime/domain/dql/From.kt

@@ -10,4 +10,9 @@ class From {
     var alias=String()
 
     var joins : ArrayList<Join> ? = null
+
+    fun addJoin(join: Join ) {
+        if (joins==null) joins = ArrayList<Join>()
+        joins!!.add(join)
+    }
 }
\ No newline at end of file

src/main/kotlin/unibz.cs.semint.kprime/domain/dql/Join.kt

@@ -4,10 +4,14 @@ import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlProperty
 
 class Join {
     @JacksonXmlProperty(isAttribute = true)
-    var joinOn=String()
+    var joinOnLeft=String()
     @JacksonXmlProperty(isAttribute = true)
-    var joinTable=String()
+    var joinLeftTable=String()
     @JacksonXmlProperty(isAttribute = true)
     var joinType=String()
+    @JacksonXmlProperty(isAttribute = true)
+    var joinOnRight=String()
+    @JacksonXmlProperty(isAttribute = true)
+    var joinRightTable=String()
 
 }
\ No newline at end of file

src/main/kotlin/unibz.cs.semint.kprime/usecase/common/SQLizeSelectUseCase.kt

 package unibz.cs.semint.kprime.usecase.common
 
-import unibz.cs.semint.kprime.domain.ddl.Database
 import unibz.cs.semint.kprime.domain.dql.*
 
 class SQLizeSelectUseCase {
@@ -37,6 +36,12 @@ class SQLizeSelectUseCase {
                 sql += "  ${from.tableName}"
                 if (!from.alias.isEmpty()) sql += " AS ${from.alias}"
                 sql += System.lineSeparator()
+                if (from.joins!=null){
+                    for (join in from.joins as ArrayList<Join>) {
+                        sql += "${join.joinType} JOIN" + System.lineSeparator()
+                        sql += "ON ${join.joinLeftTable}.${join.joinOnLeft} = ${join.joinRightTable}.${join.joinOnRight}" + System.lineSeparator()
+                    }
+                }
         }
         if (!select.where.condition.isEmpty()) {
             sql += "WHERE ${select.where.condition}"  //+ System.lineSeparator()

src/test/kotlin/unibz.cs.semint.kprime/domain/QueryTest.kt

@@ -111,6 +111,13 @@ class QueryTest {
         select.attributes.add(att)
         val from = From()
         from.tableName="Orders"
+        val join = Join()
+        join.joinLeftTable = "Orders"
+        join.joinOnLeft = "customerId"
+        join.joinRightTable = "Customer"
+        join.joinOnRight = "customerId"
+        join.joinType = "INNER"
+        from.addJoin(join)
         select.from.add(from)
         select.where.condition="a = b"
         // when
@@ -119,6 +126,47 @@ class QueryTest {
         assertEquals1("""
             SELECT "ww"
             FROM   Orders
+            INNER JOIN
+            ON Orders.customerId = Customer.customerId
+            WHERE a = b
+        """.trimIndent(),selectSql)
+    }
+
+    @Test
+    fun test_multiple_join_to_sql(){
+        // given
+        val select = Select()
+        val att = Attribute()
+        att.name="ww"
+        select.attributes.add(att)
+        val from = From()
+        from.tableName="Orders"
+        val join = Join()
+        join.joinLeftTable = "Orders"
+        join.joinOnLeft = "customerId"
+        join.joinRightTable = "Customer"
+        join.joinOnRight = "customerId"
+        join.joinType = "INNER"
+        from.addJoin(join)
+        val join2 = Join()
+        join2.joinLeftTable = "Customer"
+        join2.joinOnLeft = "orderId"
+        join2.joinRightTable = "Sales"
+        join2.joinOnRight = "orderId"
+        join2.joinType = "LEFT"
+        from.addJoin(join2)
+        select.from.add(from)
+        select.where.condition="a = b"
+        // when
+        val selectSql = SQLizeSelectUseCase().sqlize(select)
+        // then
+        assertEquals1("""
+            SELECT "ww"
+            FROM   Orders
+            INNER JOIN
+            ON Orders.customerId = Customer.customerId
+            LEFT JOIN
+            ON Customer.orderId = Sales.orderId
             WHERE a = b
         """.trimIndent(),selectSql)
     }