Java – refactoring a simple populated long method

I'm refactoring a method with more than 500 lines (don't ask me why) @ h_ 403_ 7@

public List<Hashmap> getProductData(...) {
   List<Hashmap> products = productsDao.getProductData(...);
   for (Product product: products) {
       product.put("Volume",new BigDecimanl(product.get("Height")*
              product.get("Width")*product.get("Length"));
   //over 10 more lines like the one above
      if (some condition here) {
         //20 lines worth of product.put(..,..) 
      } else {
         //20 lines worth of product.put(..,..)
      }
      //3 more if-else statements like the one above
      try {
         product.put(..,..)
      } catch (Exception e) {
         product.put("",..)
      }
      //over 8 more try-catches of the form above
   }

Solution

I came up with a simple idea to divide a method by "finding meaningful small tasks", so here are some tips: @ h_ 403_ 7@

processCollection(collection) {
// startup code
for (Item i: collection)
  processCollectionItem(i,...other args...);
// final code
}

// does a
instr 1
instr 2
instr 3
instr 4
// does b
instr 5
instr 6
instr 7
instr 8

a(...);
b(...);

map.put(a[0],b[0]);
map.put(a[1],b[1]);
...

putKeysAndValues(a,b);

putKeysAndValues(a,b) {
  for (int i=0; i<a.length; i++)
     map.put(a[i],b[i]);
}