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提前生成Hbase预分区种子,在创建Hbase表时也进行相应的预分区,同时设置预分区的个数,预分区的范围对应Hbase监控页面的Region Server的start key与End key,从而使数据能够均匀的分布于各个Region中.
private static final String[] PARTITIONS = generatPartitionSeed(); //生成3844个分区种子 public static String[] generatPartitionSeed(){ List<Character>seeds = List.newArrayList(); for(int i=‘0‘;i<=‘9‘;i++){ seeds.add((char) i); } for(int i = ‘A‘;i<=‘Z‘;i++){ seeds.add((char) i); } for(int i = ‘a‘;i<=‘z‘;i++){ seeds.add((char) i); } int k = 0; //获得总共的分区个数 String[] partions = new String[seeds.size()*seeds.get(j)); for(int i =0;i<seeds.size();i++){ for(int j=0;j<seeds.size();j++){ //两两组合成为分区start key partions[k] = StringUtil.join(seeds.get(i),seeds.get(j)); k++; } } return partions; } //按指定数量生成分区种子 public static String[] generatPartitionSeed(int limit){ int size = PARTITIONS.length; int[] space = new int[limit]; for(int pt = 0;pt<size;){ for(int j=0;j<space.length;j++){ ++space[j]; pt++; if(pt == size){ break; } } } String[] seed = new String[limit+1]; int position = 0; for(int i =0;i<space.length;i++){ seed[i] = PARTITIONS[position]; position += space[i]; } seed[seed.length -1] = PARTITIONS[PARTITIONS.length -1]; return seed; } //生成后的rowkey public static String generatRow(String str){ int i = Math.abs(str.hashCode() % PARTITION.length); return StringUtils.join(PARTITIONS[i],"-",str); } public static void main(String[] args){ String[] arr = generatPartitionSeed(100); for(int i = 0;i<arr.length;i++){ System.out.println(arr[i]); } }
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原文地址:http://www.cnblogs.com/yangsy0915/p/5527457.html