Bit of code clean-up in the Matrix class

Author: phishman3579

src/com/jwetherell/algorithms/data_structures/Matrix.java

@@ -116,57 +116,42 @@ public void set(int row, int col, T value) {
     }
 
     public Matrix<T> identity() throws Exception{
-    	if(this.rows != this.cols){
+    	if(this.rows != this.cols)
     		throw new Exception("Matrix should be a square");
-    	}
-    	
-    	T element = this.get(0, 0); 
-    	
-    	T array[][] = (T[][])new Number[this.rows][this.cols];
-    	for(int i = 0; i < this.rows; ++i){
+
+        final T element = this.get(0, 0);
+        final T zero;
+        final T one;
+    	if (element instanceof BigDecimal) {
+    	    zero = (T)BigDecimal.ZERO;
+    	    one = (T)BigDecimal.ONE;
+        } else if(element instanceof BigInteger){
+            zero = (T)BigInteger.ZERO;
+            one = (T)BigInteger.ONE;
+        } else if(element instanceof Long){
+            zero = (T)new Long(0);
+            one = (T)new Long(1);
+        } else if(element instanceof Double){
+            zero = (T)new Double(0);
+            one = (T)new Double(1);
+        } else if(element instanceof Float){
+            zero = (T)new Float(0);
+            one = (T)new Float(1);
+        } else {
+            zero = (T)new Integer(0);
+            one = (T)new Integer(1);
+        }
+
+    	final T array[][] = (T[][])new Number[this.rows][this.cols];
+    	for(int i = 0; i < this.rows; ++i) {
     		for(int j = 0 ; j < this.cols; ++j){
-    			if(element instanceof BigDecimal){
-        			array[i][j] = (T)BigDecimal.ZERO;
-        		}
-        		else if(element instanceof BigInteger){
-        			array[i][j] = (T)BigInteger.ZERO;
-        		}
-        		else if(element instanceof Long){
-        			array[i][j] = (T)new Long(0);
-        		}
-        		else if(element instanceof Double){
-        			array[i][j] = (T)new Double(0);
-        		}
-        		else if(element instanceof Float){
-        			array[i][j]= (T)new Float(0);
-        		}
-        		else{
-        			array[i][j] = (T)new Integer(0);
-        		}
+    		    array[i][j] = zero;
     		}
     	}
-    	   	
-    	Matrix<T> identityMatrix = new Matrix<T>(this.rows, this.cols, array);
-    	
+
+    	final Matrix<T> identityMatrix = new Matrix<T>(this.rows, this.cols, array);
     	for(int i = 0; i < this.rows;++i){
-    		if(element instanceof BigDecimal){
-    			identityMatrix.set(i, i, (T)BigDecimal.ONE);
-    		}
-    		else if(element instanceof BigInteger){
-    			identityMatrix.set(i,i,(T)BigInteger.ONE);
-    		}
-    		else if(element instanceof Long){
-    			identityMatrix.set(i, i, (T)new Long(1));
-    		}
-    		else if(element instanceof Double){
-    			identityMatrix.set(i, i, (T)new Double(1));
-    		}
-    		else if(element instanceof Float){
-    			identityMatrix.set(i, i, (T)new Float(1));
-    		}
-    		else{
-    			identityMatrix.set(i, i, (T)new Integer(1));
-    		}
+    	    identityMatrix.set(i, i, one);
     	}
     	return identityMatrix;
     }