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POHow do I loop into the ArrayList's Block's Tuple?
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  1. POHow do I loop into the ArrayList's Block's Tuple?
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    copied!<p>I am sorry if the code is long. <strong>Block</strong> and <strong>Tuple</strong> are self defined classes. Their attributes are protected. <strong>Block</strong> contains a <strong>ArrayList</strong> of <strong>Tuples</strong>. <strong>Tuple</strong> has attribute int <strong>Key</strong> and String <strong>value</strong></p> <p>I have ArrayList[] bucketLstS and Block[] bucketBlocksS</p> <pre><code>ArrayList[] bucketLstS = new ArrayList[Setting.memorySize - 1]; Block[] bucketBlocksS = new Block[Setting.memorySize - 1]; for (int i = 0; i &lt; bucketBlocksS.length; i++) { bucketLstS[i] = new ArrayList&lt;Tuple&gt;(); bucketBlocksS[i] = new Block(); } //Get individual relS keys RelationLoader sLoader = relS.getRelationLoader(); while (sLoader.hasNext()) { Block[] blocks = sLoader.loadNextBlocks(1); for (Block b : blocks) { numIO++; if (b != null) { for (Tuple t : b.tupleLst) { //Hash the key to determine which Bucket bucketIdx = t.key % (Setting.memorySize - 2); //System.out.println(bucketBlocksS[bucketIdx].getNumTuples()); //check if the block is already full if (bucketBlocksS[bucketIdx].getNumTuples() &gt;= Setting.blockFactor) { bucketLstS[bucketIdx].add(bucketBlocksS[bucketIdx]); bucketBlocksS[bucketIdx] = new Block(); blkNum++; } bucketBlocksS[bucketIdx].insertTuple(t); } } } }//end while </code></pre> <p>The question is that I need to loop into each Block, so that I can access each Tuple's <strong>Key</strong> and <strong>value</strong> I tried this:</p> <pre><code> for (int i = 0; i &lt; bucketLstS.length; i++) { System.out.println(i + " " + bucketLstS[i]); for (int j = 0; j &lt; bucketLstS[i].size(); j++) { //Access a Block in Block Array System.out.println(j + " " + bucketLstS[i].get(j)); } } </code></pre> <p>But then I am stuck. The output is like:</p> <pre><code>0 [project2.Block@558fee4f, project2.Block@5c66b06b, project2.Block@59c87031, project2.Block@763dcf03, project2.Block@53e20a9a, project2.Block@1d262f7c, project2.Block@35f784d7, project2.Block@d325aef, project2.Block@64f007ad] 0 project2.Block@558fee4f 1 project2.Block@5c66b06b 2 project2.Block@59c87031 3 project2.Block@763dcf03 4 project2.Block@53e20a9a 5 project2.Block@1d262f7c 6 project2.Block@35f784d7 7 project2.Block@d325aef 8 project2.Block@64f007ad </code></pre> <p>But how to I get into the Tuple of a Block to get to the key? (To obtain key, can use Tuple.key)</p> <p>Following is the Class for Block</p> <pre><code>import java.util.ArrayList; public class Block { /** * List of tuples contained in this block */ protected ArrayList&lt;Tuple&gt; tupleLst; public Block(){ this.tupleLst=new ArrayList&lt;Tuple&gt;(Setting.blockFactor); } /** * Insert a tuple t to this block * @param t is a tuple to be inserted to this block * @return true if tuple t is successfully inserted into this block and false if the block is full */ //One tupleLst can store up to "10" tuples public boolean insertTuple(Tuple t){ if(tupleLst.size()&lt;Setting.blockFactor){ tupleLst.add(t); return true; } return false; } /** * @return number of tuples stored in this block */ public int getNumTuples(){ return tupleLst.size(); } /** * Print this block * @param printTuple is a flag to indicate whether the details of the tuples are printed */ public void print(boolean printTuple){ System.out.println("[BlockSize: "+getNumTuples()+"]"); if(printTuple){ for(Tuple t:tupleLst){ System.out.println(t); } } } </code></pre>
 

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