JercD1p9

1   public void marshall() throws IOException {
2        /* not yet implemented */
3    	
4    	// find the primary key column of the table, and its index if it exists
5    	Column pkey = this.table.primaryKeyColumn();
6    	
7    	int pkey_index = -10;
8    	Object pkey_value = null;
9    	
10    	if (pkey != null) {
11    		pkey_index = pkey.getIndex();
12    		pkey_value = this.values[pkey_index];
13    	}
14    	
15    	
16    	
17    	
18    	// Assigning the key value
19    	TupleOutput keyBuffer = null;
20    	if (pkey!= null) {
21    		keyBuffer = new TupleOutput();
22    		if (pkey_value.getClass().equals(Integer.class)) { 
23    			keyBuffer.writeInt((Integer)pkey_value);
24    		} else {
25    			keyBuffer.writeBytes((String)pkey_value);
26    		}
27    		byte[] bytes = keyBuffer.getBufferBytes();
28    		int numBytes = keyBuffer.getBufferLength();
29    		DatabaseEntry key_to_insert = new DatabaseEntry(bytes, 0, numBytes);
30    		this.key = key_to_insert;
31    	}
32    	
33    	
34    	// Assigning the data value
35    	
36    	int num_headers = this.values.length + 1;
37    	int[] headers = new int[num_headers];
38    	
39    	// to accomplish this, I'm going to create the header of offsets as if there were no primary key,
40    	// and then subsequently perform elementwise subtraction if there is a key.
41    	
42    	for (int i = 0; i < num_headers; i++) {
43    		// Starting offset for all headers, but will have to move if the primary key is the first term
44    		if (i == 0) {
45    			headers[i] = num_headers * 4;
46    		} else {
47    			// down here I define each length of header by class.
48    			if (this.values[i-1].getClass().equals(Integer.class)) {
49    				headers[i] = headers[i-1] + 4;
50    			} else if (this.values[i-1].getClass().equals(Double.class)) {
51    				headers[i] = headers[i-1] + 8;
52    			} else if (this.values[i-1].getClass().equals(Character.class)) {
53    				headers[i] = headers[i-1] + 1;
54    			} else {
55    				headers[i] = headers[i-1] + ((String)this.values[i-1]).length();
56    			}
57    		}
58    	}
59
60    	
61    	
62    	// manipulation of some headers due to the presence of a primary key
63    	if (pkey != null) {
64    		
65    		int to_subtract = 0;
66    		
67    		if (pkey_value.getClass().equals(Integer.class))
68    			to_subtract = 4;
69    		else if (pkey_value.getClass().equals(Double.class))
70    			to_subtract = 8;
71    		else if (pkey_value.getClass().equals(Character.class)) 
72    			to_subtract = 1;
73    		else 
74    			to_subtract = ((String)pkey_value).length();
75    			
76    		for (int i = 0; i<num_headers; i++) {
77    			if (i == pkey_index) {
78    				headers[i] = -2;
79    			} else if (i>pkey_index) {
80    				headers[i] -= to_subtract;
81    			}
82    		}
83    	}
84    	
85    	//This is where the marshalling of the data occurs
86    	
87    	TupleOutput valueBuffer = new TupleOutput();
88    	//giving the headers of metadata
89    	for (int i = 0; i<num_headers; i++) {
90    		valueBuffer.writeInt(headers[i]);
91    	}
92    	// writing the data
93    	for (int i = 0; i<this.values.length; i++) {
94    		// we don't want to include our primary key in the row of marshalled data
95    		if (i == pkey_index) {
96    			continue;
97    		// the rest of these if statements separate different write methods by class
98    		} else if (this.values[i].getClass().equals(Integer.class)) {
99    			valueBuffer.writeInt((Integer)this.values[i]);
100    		} else if (this.values[i].getClass().equals(Double.class)) {
101    			valueBuffer.writeDouble((Double)this.values[i]);
102    		} else if (this.values[i].getClass().equals(Character.class)) {
103    			valueBuffer.writeChar((Character)this.values[i]);
104    		} else {
105    			valueBuffer.writeBytes((String)this.values[i]);
106    		}
107    	}
108    	valueBuffer.close();
109    	
110    	byte[] bytes = valueBuffer.getBufferBytes();
111    	int numBytes = valueBuffer.getBufferLength();
112    	DatabaseEntry value = new DatabaseEntry(bytes, 0, numBytes);
113    	this.data = value;
114    	
115    	
116    }