• Java链接HBASE数据库,创建一个表,删除一张表,修改表,输出插入,修改,数据删除,数据获取,显示表信息,过滤查询,分页查询,地理hash


    准备工作 
    1、创建Java的Maven项目 
    创建好的目录结构如下: 
    这里写图片描述

    另外注意junit的版本,最好不要太高,最开始笔者使用的junit4.12的,发现运行的时候会报错。最后把Junit的版本改成4.7的之后,问题解决了。

    创建测试工具类HbaseDemo,为了保证能够让Hbase运行,需要最开始写出如下配置:

    package toto.com.hbase;
    
    import java.util.ArrayList;
    import java.util.Iterator;
    
    import org.apache.hadoop.conf.Configuration;
    import org.apache.hadoop.hbase.Cell;
    import org.apache.hadoop.hbase.CellScanner;
    import org.apache.hadoop.hbase.HBaseConfiguration;
    import org.apache.hadoop.hbase.HColumnDescriptor;
    import org.apache.hadoop.hbase.HTableDescriptor;
    import org.apache.hadoop.hbase.TableName;
    import org.apache.hadoop.hbase.client.Admin;
    import org.apache.hadoop.hbase.client.Connection;
    import org.apache.hadoop.hbase.client.ConnectionFactory;
    import org.apache.hadoop.hbase.client.Delete;
    import org.apache.hadoop.hbase.client.Get;
    import org.apache.hadoop.hbase.client.Put;
    import org.apache.hadoop.hbase.client.Result;
    import org.apache.hadoop.hbase.client.ResultScanner;
    import org.apache.hadoop.hbase.client.Scan;
    import org.apache.hadoop.hbase.client.Table;
    import org.apache.hadoop.hbase.filter.BinaryComparator;
    import org.apache.hadoop.hbase.filter.BinaryPrefixComparator;
    import org.apache.hadoop.hbase.filter.ByteArrayComparable;
    import org.apache.hadoop.hbase.filter.ColumnPrefixFilter;
    import org.apache.hadoop.hbase.filter.CompareFilter.CompareOp;
    import org.apache.hadoop.hbase.filter.FamilyFilter;
    import org.apache.hadoop.hbase.filter.Filter;
    import org.apache.hadoop.hbase.filter.FilterList;
    import org.apache.hadoop.hbase.filter.FilterList.Operator;
    import org.apache.hadoop.hbase.filter.MultipleColumnPrefixFilter;
    import org.apache.hadoop.hbase.filter.PageFilter;
    import org.apache.hadoop.hbase.filter.PrefixFilter;
    import org.apache.hadoop.hbase.filter.QualifierFilter;
    import org.apache.hadoop.hbase.filter.RegexStringComparator;
    import org.apache.hadoop.hbase.filter.RowFilter;
    import org.apache.hadoop.hbase.filter.SingleColumnValueFilter;
    import org.apache.hadoop.hbase.filter.SubstringComparator;
    import org.apache.hadoop.hbase.regionserver.BloomType;
    import org.apache.hadoop.hbase.util.Bytes;
    import org.junit.Before;
    import org.junit.Test;
    
    /**
     * 代码说明
     *
     * @author tuzq
     * @create 2017-06-22 20:48
     */
    public class HbaseDemo {
        private Configuration conf = null;
        private Connection conn = null;
    
        @Before
        public void init() throws Exception {
            conf = HBaseConfiguration.create();
            conn = ConnectionFactory.createConnection();
        }
    }
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    2、创建一个表

    @Test
        public void testCreate() throws Exception {
            //获取一个表管理器
            Admin admin = conn.getAdmin();
            //表的描述器
            HTableDescriptor htd = new HTableDescriptor(TableName.valueOf("t_user_info"));
    
            //列族的描述器
            HColumnDescriptor hcd1 = new HColumnDescriptor("base_info");
            //BloomType.ROW 快速搜索一个数据在哪个文件块中
            hcd1.setBloomFilterType(BloomType.ROW).setVersions(1,3);
    
            //列族的描述器
            HColumnDescriptor hcd2 = new HColumnDescriptor("extra_info");
            hcd2.setBloomFilterType(BloomType.ROW).setVersions(1,3);
    
            //添加列族
            htd.addFamily(hcd1).addFamily(hcd2);
    
            //创建表
            admin.createTable(htd);
            admin.close();
            conn.close();
        }
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    运行后的成功的结果状态: 
    这里写图片描述 
    进入hbase中,查看数据信息 
    这里写图片描述

    3、删除一张表

    @Test
        public void testDrop() throws Exception {
            Admin admin = conn.getAdmin();
            admin.disableTable(TableName.valueOf("t_user_info2"));
            admin.deleteTable(TableName.valueOf("t_user_info2"));
            admin.close();
            conn.close();
        }
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    执行后的效果如下: 
    这里写图片描述 
    进入HBASE中查看效果: 
    这里写图片描述

    4.其它操作api

    @Test
        public void testModify() throws Exception {
            Admin admin = conn.getAdmin();
            // 修改已有ColumnFamily
            HTableDescriptor table = admin.getTableDescriptor(TableName.valueOf("t_user_info"));
            HColumnDescriptor f2 = table.getFamily("extra_info".getBytes());
            f2.setBloomFilterType(BloomType.ROWCOL);
            // 添加新的ColumnFamily
            table.addFamily(new HColumnDescriptor("other_info"));
    
            admin.modifyTable(TableName.valueOf("t_user_info"), table);
            admin.close();
            conn.close();
        }
    
        /**
         * 插入/修改 数据
         * @throws Exception
         */
        @Test
        public void testPut() throws Exception {
            Table table = conn.getTable(TableName.valueOf("t_user_info"));
    
            ArrayList<Put> puts = new ArrayList<Put>();
    
            Put put01 = new Put(Bytes.toBytes("user001"));
            put01.addColumn(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("zhangsan"));
    
            Put put02 = new Put("user001".getBytes());
            put02.addColumn(Bytes.toBytes("base_info"), Bytes.toBytes("password"), Bytes.toBytes("123456"));
    
            Put put03 = new Put("user002".getBytes());
            put03.addColumn(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("lisi"));
            put03.addColumn(Bytes.toBytes("extra_info"), Bytes.toBytes("married"), Bytes.toBytes("false"));
    
            Put put04 = new Put("zhang_sh_01".getBytes());
            put04.addColumn(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("zhang01"));
            put04.addColumn(Bytes.toBytes("extra_info"), Bytes.toBytes("married"), Bytes.toBytes("false"));
    
            Put put05 = new Put("zhang_sh_02".getBytes());
            put05.addColumn(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("zhang02"));
            put05.addColumn(Bytes.toBytes("extra_info"), Bytes.toBytes("married"), Bytes.toBytes("false"));
    
            Put put06 = new Put("liu_sh_01".getBytes());
            put06.addColumn(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("liu01"));
            put06.addColumn(Bytes.toBytes("extra_info"), Bytes.toBytes("married"), Bytes.toBytes("false"));
    
            Put put07 = new Put("zhang_bj_01".getBytes());
            put07.addColumn(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("zhang03"));
            put07.addColumn(Bytes.toBytes("extra_info"), Bytes.toBytes("married"), Bytes.toBytes("false"));
    
            Put put08 = new Put("zhang_bj_01".getBytes());
            put08.addColumn(Bytes.toBytes("base_info"), Bytes.toBytes("username"), Bytes.toBytes("zhang04"));
            put08.addColumn(Bytes.toBytes("extra_info"), Bytes.toBytes("married"), Bytes.toBytes("false"));
    
            puts.add(put01);
            puts.add(put02);
            puts.add(put03);
            puts.add(put04);
            puts.add(put05);
            puts.add(put06);
            puts.add(put07);
            puts.add(put08);
    
            table.put(puts);
            table.close();
            conn.close();
        }
    
        @Test
        public void testDel() throws Exception {
            Table t_user_info = conn.getTable(TableName.valueOf("t_user_info"));
            Delete delete = new Delete("user001".getBytes());
            delete.addColumn("base_info".getBytes(), "password".getBytes());
            t_user_info.delete(delete);
    
            t_user_info.close();
            conn.close();
        }
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    @Test
        public void testGet() throws Exception {
            Table table = conn.getTable(TableName.valueOf("t_user_info"));
    
            Get get = new Get("user001".getBytes());
            Result result = table.get(get);
            CellScanner cellScanner = result.cellScanner();
            while(cellScanner.advance()) {
                Cell current = cellScanner.current();
                byte[] familyArray = current.getFamilyArray();
                byte[] qualifierArray = current.getQualifierArray();
                byte[] valueArray = current.getValueArray();
    
                System.out.println(new String(familyArray,current.getFamilyLength(),current.getFamilyLength()));
                System.out.print(":" + new String(qualifierArray, current.getQualifierOffset(), current.getQualifierLength()));
                System.out.print(":" + new String(qualifierArray, current.getQualifierOffset(), current.getQualifierLength()));
            }
            table.close();
            table.close();
        }
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    运行结果: 
    这里写图片描述

    @Test
        public void testScan() throws Exception {
            Table t_user_info = conn.getTable(TableName.valueOf("t_user_info"));
            Scan scan = new Scan();
    
            ResultScanner scanner = t_user_info.getScanner(scan);
            Iterator<Result> iter = scanner.iterator();
            while (iter.hasNext()) {
                Result result = iter.next();
                CellScanner cellScanner = result.cellScanner();
                while(cellScanner.advance()) {
                    Cell current = cellScanner.current();
                    byte[] familyArray = current.getFamilyArray();
                    byte[] valueArray = current.getValueArray();
                    byte[] qualifierArray = current.getQualifierArray();
                    byte[] rowArray = current.getRowArray();
    
                    System.out.println(new String(rowArray, current.getRowOffset(), current.getRowLength()));
                    System.out.print(new String(familyArray, current.getFamilyOffset(), current.getFamilyLength()));
                    System.out.print(":" + new String(qualifierArray, current.getQualifierOffset(), current.getQualifierLength()));
                    System.out.println(" " + new String(valueArray, current.getValueOffset(), current.getValueLength()));
                }
                System.out.println("-----------------------");
            }
        }
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    运行结果: 
    这里写图片描述

    其它代码(过滤,扫描,分页查询):

    /**
         * 下面的内容一个注释一个注释的放开,然后可以看到过滤后的效果
         * @throws Exception
         */
        @Test
        public void testFilter() throws Exception {
            // 针对行键的前缀过滤器
            /*Filter pf = new PrefixFilter(Bytes.toBytes("liu"));
            testScan(pf);*/
    
            // 行过滤器
            /*RowFilter rf1 = new RowFilter(CompareOp.LESS, new BinaryComparator(Bytes.toBytes("user001")));
            RowFilter rf2 = new RowFilter(CompareOp.EQUAL, new SubstringComparator("00"));
            testScan(rf1);
            System.out.println("**********");
            testScan(rf2);*/
    
            // 针对指定一个列的value来过滤
            /*SingleColumnValueFilter scvf = new SingleColumnValueFilter("base_info".getBytes(), "password".getBytes(), CompareOp.EQUAL, "123456".getBytes());
            scvf.setFilterIfMissing(true);   // 如果指定的列缺失,则也过滤掉
            testScan(scvf);*/
    
            /*ByteArrayComparable comparator1 = new RegexStringComparator("^zhang");
            ByteArrayComparable comparator2 = new SubstringComparator("ang");
            SingleColumnValueFilter scvf = new SingleColumnValueFilter("base_info".getBytes(), "username".getBytes(), CompareOp.EQUAL, comparator1);
            testScan(scvf);*/
    
            // 针对列族名的过滤器
            /*FamilyFilter ff1 = new FamilyFilter(CompareOp.EQUAL, new BinaryComparator(Bytes.toBytes("inf")));
            FamilyFilter ff2 = new FamilyFilter(CompareOp.EQUAL, new BinaryPrefixComparator(Bytes.toBytes("base")));
            testScan(ff1);*/
    
            // 针对列名的过滤器
            /*QualifierFilter qf = new QualifierFilter(CompareOp.EQUAL, new BinaryComparator(Bytes.toBytes("password")));
            QualifierFilter qf2 = new QualifierFilter(CompareOp.EQUAL, new BinaryPrefixComparator(Bytes.toBytes("us")));
            testScan(qf);*/
    
            // 跟SingleColumnValueFilter结果不同,只返回符合条件的该column
            /*ColumnPrefixFilter cf = new ColumnPrefixFilter("passw".getBytes());
            testScan(cf);*/
    
            /*byte[][] prefixes = new byte[][] { Bytes.toBytes("username"),Bytes.toBytes("password") };
            MultipleColumnPrefixFilter mcf = new MultipleColumnPrefixFilter(prefixes);
            testScan(mcf);*/
    
            /*FamilyFilter ff2 = new FamilyFilter(CompareOp.EQUAL, new BinaryPrefixComparator(Bytes.toBytes("base")));
            ColumnPrefixFilter cf = new ColumnPrefixFilter("passw".getBytes());
            FilterList filterList = new FilterList(Operator.MUST_PASS_ALL);
            filterList.addFilter(ff2);
            filterList.addFilter(cf);
            testScan(filterList);*/
        }
    
        public void testScan(Filter filter) throws Exception {
    
            Table t_user_info = conn.getTable(TableName.valueOf("t_user_info"));
    
            Scan scan = new Scan();
            scan.setFilter(filter);
            ResultScanner scanner = t_user_info.getScanner(scan);
    
            Iterator<Result> iter = scanner.iterator();
            while (iter.hasNext()) {
                Result result = iter.next();
                CellScanner cellScanner = result.cellScanner();
                while (cellScanner.advance()) {
                    Cell current = cellScanner.current();
                    byte[] familyArray = current.getFamilyArray();
                    byte[] valueArray = current.getValueArray();
                    byte[] qualifierArray = current.getQualifierArray();
                    byte[] rowArray = current.getRowArray();
    
                    System.out.println(new String(rowArray, current.getRowOffset(), current.getRowLength()));
                    System.out.print(new String(familyArray, current.getFamilyOffset(), current.getFamilyLength()));
                    System.out.print(":" + new String(qualifierArray, current.getQualifierOffset(), current.getQualifierLength()));
                    System.out.println(" " + new String(valueArray, current.getValueOffset(), current.getValueLength()));
                }
                System.out.println("-----------------------");
            }
        }
    
        /**
         * 分页查询
         *
         * @throws Exception
         */
        @Test
        public void pageScan() throws Exception{
            final byte[] POSTFIX = new byte[] { 0x00 };
            Table table = conn.getTable(TableName.valueOf("t_user_info"));
            Filter filter = new PageFilter(3);   // 一次需要获取一页的条数
            byte[] lastRow = null;
            int totalRows = 0;
            while (true) {
                Scan scan = new Scan();
                scan.setFilter(filter);
                if(lastRow != null){
                    byte[] startRow = Bytes.add(lastRow,POSTFIX);   //设置本次查询的起始行键
                    scan.setStartRow(startRow);
                }
                ResultScanner scanner = table.getScanner(scan);
                int localRows = 0;
                Result result;
                while((result = scanner.next()) != null){
                    System.out.println(localRows++ + ":" + result);
                    totalRows ++;
                    lastRow = result.getRow();
                }
                scanner.close();
                if(localRows == 0) break;
                Thread.sleep(2000);
            }
            System.out.println("total rows:" + totalRows);
        }
    
        public static void main(String[] args) throws Exception {
            HbaseDemo demo = new HbaseDemo();
            demo.init();
            demo.testScan();
        }
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    地理hash的代码:

    
    import java.util.BitSet;
    import java.util.HashMap;
    
    public class Geohash {
    
        private static int numbits = 6 * 5;
        final static char[] digits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'j', 'k', 'm', 'n', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z' };
    
        final static HashMap<Character, Integer> lookup = new HashMap<Character, Integer>();
        static {
            int i = 0;
            for (char c : digits)
                lookup.put(c, i++);
        }http://www.woaipu.com/shops/zuzhuan/61406
    
        public double[] decode(String geohash) {
            StringBuilder buffer = new StringBuilder();
            for (char c : geohash.toCharArray()) {
    
                int i = lookup.get(c) + 32;
                buffer.append(Integer.toString(i, 2).substring(1));
            }
    
            BitSet lonset = new BitSet();
            BitSet latset = new BitSet();
    http://www.woaipu.com/shops/zuzhuan/61406
            // even bits
            int j = 0;
            for (int i = 0; i < numbits * 2; i += 2) {
                boolean isSet = false;
                if (i < buffer.length())
                    isSet = buffer.charAt(i) == '1';
                lonset.set(j++, isSet);
            }
    
            // odd bits
            j = 0;
            for (int i = 1; i < numbits * 2; i += 2) {
                boolean isSet = false;
                if (i < buffer.length())
                    isSet = buffer.charAt(i) == '1';
                latset.set(j++, isSet);
            }
            // 中国地理坐标:东经73°至东经135°,北纬4°至北纬53°
            double lon = decode(lonset, 70, 140);
            double lat = decode(latset, 0, 60);
    
            return new double[] { lat, lon };
        }
    
        private double decode(BitSet bs, double floor, double ceiling) {
            double mid = 0;
            for (int i = 0; i < bs.length(); i++) {
                mid = (floor + ceiling) / 2;
                if (bs.get(i))
                    floor = mid;
                else
                    ceiling = mid;
            }
            return mid;
        }
    
        public String encode(double lat, double lon) {
            BitSet latbits = getBits(lat, 0, 60);
            BitSet lonbits = getBits(lon, 70, 140);
            StringBuilder buffer = new StringBuilder();
            for (int i = 0; i < numbits; i++) {
                buffer.append((lonbits.get(i)) ? '1' : '0');
                buffer.append((latbits.get(i)) ? '1' : '0');
            }
            return base32(Long.parseLong(buffer.toString(), 2));
        }
    
        private BitSet getBits(double lat, double floor, double ceiling) {
            BitSet buffer = new BitSet(numbits);
            for (int i = 0; i < numbits; i++) {
                double mid = (floor + ceiling) / 2;
                if (lat >= mid) {
                    buffer.set(i);
                    floor = mid;
                } else {
                    ceiling = mid;
                }
            }
            return buffer;
        }
    
        public static String base32(long i) {
            char[] buf = new char[65];
            int charPos = 64;
            boolean negative = (i < 0);
            if (!negative)
                i = -i;
            while (i <= -32) {
                buf[charPos--] = digits[(int) (-(i % 32))];
                i /= 32;http://www.woaipu.com/shops/zuzhuan/61406
            }http://www.woaipu.com/shops/zuzhuan/61406
            buf[charPos] = digits[(int) (-i)];
    
            if (negative)
                buf[--charPos] = '-';
            return new String(buf, charPos, (65 - charPos));
        }
    
        public static void main(String[] args) {
            Geohash geohash = new Geohash();
            String encode1 = geohash.encode(123.3345, 78.2247);
            String encode2 = geohash.encode(123.3446, 78.2249);
            String encode3 = geohash.encode(120.3346, 108.2249);
            System.out.println(encode1);
            System.out.println(encode2);
            System.out.println(encode3);
        }
    http://www.woaipu.com/shops/zuzhuan/61406
    http://www.woaipu.com/shops/zuzhuan/61406
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  • 原文地址:https://www.cnblogs.com/sy646et/p/7197678.html
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