Changeset 26 for trunk/fmgVen/src/com/fmguler

Timestamp:

Jan 2, 2011, 8:51:21 PM (14 years ago)

Author:

fmguler

Message:

Refs #3 - Ven.save() is transferred to the new package. Save use case is completed. Convert.toDB() converts camel case object names to database names with underscores. Unchecked VenException is thrown by Ven methods. Liquibase changelog (test-db-changelog.xml) is changed to include only a simple object to test save operation. It creates a sample database table and inserts a sample row. On rollback it removes sample data. Using liquibase, Sample.java builds database, tests save operation and rolls back.

QueryGenerator generates insert and update queries for save and generates sequence query to assign ids to new objects. Ven calls query generator and runs the query using spring jdbc template.

Old codebase updated to run at Java 1.4

Location:

trunk/fmgVen/src/com/fmguler/ven

Files:

• QueryGenerator.java (modified) (3 diffs)
• Ven.java (modified) (2 diffs)
• VenException.java (added)
• util (added)
• util/Convert.java (added)

trunk/fmgVen/src/com/fmguler/ven/QueryGenerator.java

@@ -18 +18 @@
 package com.fmguler.ven;
 
+import com.fmguler.ven.util.Convert;
+import java.beans.PropertyDescriptor;
+import java.util.Date;
 import java.util.HashSet;
 import java.util.Set;
+import org.springframework.beans.BeanWrapper;
+import org.springframework.beans.BeanWrapperImpl;
 
 /**
@@ -27 +32 @@
 public class QueryGenerator {
     private Set domainPackages;
+    private Set dbClasses;
 
     public QueryGenerator() {
         domainPackages = new HashSet();
+        dbClasses = new HashSet();
+        //the predefined database classes;
+        this.dbClasses.add(Integer.class);
+        this.dbClasses.add(String.class);
+        this.dbClasses.add(Date.class);
+        this.dbClasses.add(Double.class);
+        this.dbClasses.add(Boolean.class);
     }
 
@@ -40 +53 @@
     }
 
-    public String generateUpdateQuery() {
-        return null;
+    public String generateInsertQuery(Object object) throws VenException {
+        BeanWrapper wr = new BeanWrapperImpl(object);
+        String objectName = Convert.toSimpleName(object.getClass().getName());
+        String tableName = Convert.toDB(objectName);
+        PropertyDescriptor[] pdArr = wr.getPropertyDescriptors();
+
+        //generate insert query
+        StringBuffer query = new StringBuffer("insert into " + tableName + "(");
+        StringBuffer values = new StringBuffer(" values(");
+        for (int i = 0; i < pdArr.length; i++) {
+            Class fieldClass = pdArr[i].getPropertyType(); //field class
+            String columnName = Convert.toDB(pdArr[i].getName()); //column name
+            String fieldName = pdArr[i].getName(); //field name
+            //if (fieldName.equals("id")) continue; //remove if it does not break the sequence
+            if (dbClasses.contains(fieldClass)) { //direct database field (Integer,String,Date, etc)
+                query.append(columnName);
+                query.append(",");
+                values.append(":").append(fieldName);
+                values.append(",");
+            }
+            if (fieldClass.getPackage() != null && domainPackages.contains(fieldClass.getPackage().getName())) { //object
+                query.append(Convert.toDB(fieldName)).append("_id");
+                query.append(",");
+                values.append(":").append(fieldName).append(".id");
+                values.append(",");
+            }
+        }
+        query.deleteCharAt(query.length() - 1);
+        query.append(")");
+        values.deleteCharAt(values.length() - 1);
+        values.append(");");
+        query.append(values);
+
+        return query.toString();
     }
 
-    //SETTERS-------------------------------------------------------------------
+    /**
+     * Generates insert/update query
+     * @return the insert update SQL query
+     */
+    public String generateUpdateQuery(Object object) throws VenException {
+        BeanWrapper wr = new BeanWrapperImpl(object);
+        String objectName = Convert.toSimpleName(object.getClass().getName());
+        String tableName = Convert.toDB(objectName);
+        PropertyDescriptor[] pdArr = wr.getPropertyDescriptors();
+
+        StringBuffer query = new StringBuffer("update " + tableName + " set ");
+        for (int i = 0; i < pdArr.length; i++) {
+            Class fieldClass = pdArr[i].getPropertyType(); //field class
+            String columnName = Convert.toDB(pdArr[i].getName()); //column name
+            String fieldName = pdArr[i].getName(); //field name
+            if (dbClasses.contains(fieldClass)) { //direct database field (Integer,String,Date, etc)
+                query.append(columnName).append("=:").append(fieldName);
+                query.append(",");
+            }
+            if (fieldClass.getPackage() != null && domainPackages.contains(fieldClass.getPackage().getName())) { //object
+                query.append(columnName).append("_id=:").append(fieldName).append(".id");
+                query.append(",");
+            }
+        }
+        query.deleteCharAt(query.length() - 1);
+        query.append(" where id = :id ;"); //TODO: remove the last comma
+        return query.toString();
+    }
+
+    public String generateSequenceQuery(Object object) throws VenException {
+        String objectName = Convert.toSimpleName(object.getClass().getName());
+        String tableName = Convert.toDB(objectName);
+        return "select nextval('" + tableName + "_id_seq');";
+    }
+
+    //--------------------------------------------------------------------------
+    //SETTERS
     public void addDomainPackage(String domainPackage) {
         domainPackages.add(domainPackage);

trunk/fmgVen/src/com/fmguler/ven/Ven.java

@@ -18 +18 @@
 package com.fmguler.ven;
 
+import java.util.HashMap;
 import java.util.List;
 import javax.sql.DataSource;
+import org.springframework.beans.BeanWrapper;
+import org.springframework.beans.BeanWrapperImpl;
+import org.springframework.jdbc.core.namedparam.BeanPropertySqlParameterSource;
 import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate;
+import org.springframework.jdbc.core.namedparam.SqlParameterSource;
 
 /**
@@ -44 +49 @@
     }
 
-    public Object get(int no, Class objectClass) {
+    public Object get(int id, Class objectClass) {
         return null;
     }
 
+    /**
+     * Save the object. If it has a "id" property it will be updated.
+     * It will be inserted otherwise.
+     * <p>
+     * The object will be saved to a table with the same name as the object,
+     * The fields of object will be mapped to the table fields.
+     * 
+     * @param object the object to be saved
+     */
     public void save(Object object) {
+        String query = null;
+
+        if (isObjectNew(object)) {
+            //if this is a new object assign a new id first
+            generateId(object);
+            query = generator.generateInsertQuery(object);
+        } else {
+            query = generator.generateUpdateQuery(object);
+        }
+
+        //execute the insert/update query
+        SqlParameterSource parameterSource = new BeanPropertySqlParameterSource(object);
+        template.update(query, parameterSource);
     }
 
-    public void delete(int no, Class objectClass) {
+    public void delete(int id, Class objectClass) {
     }
 
-    //SETTERS-------------------------------------------------------------------
+    //--------------------------------------------------------------------------
+    //PRIVATE METHODS
+    //return true if the object id is zero or null false otherwise
+    private boolean isObjectNew(Object object) throws VenException {
+        BeanWrapper beanWrapper = new BeanWrapperImpl(object);
+        Object objectId = beanWrapper.getPropertyValue("id"); 
+        if (objectId == null) return true;
+        if (!(objectId instanceof Integer)) throw new VenException(VenException.EC_GENERATOR_OBJECT_ID_TYPE_INVALID);
+        return ((Integer)objectId).intValue() == 0;
+    }
+
+    //set new object id
+    private void generateId(Object object) {
+        Integer newObjectId = new Integer(template.queryForInt(generator.generateSequenceQuery(object), new HashMap()));
+        BeanWrapper beanWrapper = new BeanWrapperImpl(object);
+        beanWrapper.setPropertyValue("id", newObjectId);
+    }
+
+    //--------------------------------------------------------------------------
+    //SETTERS
     public void setDataSource(DataSource dataSource) {
         if (dataSource == null) throw new RuntimeException("fmgVen - DataSource cannot be null");