Hadoop项目实战
Posted 陈驰字新宇
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FlowBean.java:
package cn.itcast.hadoop.mr.flowsum; import java.io.DataInput; import java.io.DataOutput; import java.io.IOException; import org.apache.hadoop.io.Writable; import org.apache.hadoop.io.WritableComparable; public class FlowBean implements WritableComparable<FlowBean>{ private String phoneNB; private long up_flow; private long d_flow; private long s_flow; //在反序列化时，反射机制需要调用空参构造函数，所以显示定义了一个空参构造函数 public FlowBean(){} //为了对象数据的初始化方便，加入一个带参的构造函数 public FlowBean(String phoneNB, long up_flow, long d_flow) { this.phoneNB = phoneNB; this.up_flow = up_flow; this.d_flow = d_flow; this.s_flow = up_flow + d_flow; } public void set(String phoneNB, long up_flow, long d_flow) { this.phoneNB = phoneNB; this.up_flow = up_flow; this.d_flow = d_flow; this.s_flow = up_flow + d_flow; } public String getPhoneNB() { return phoneNB; } public void setPhoneNB(String phoneNB) { this.phoneNB = phoneNB; } public long getUp_flow() { return up_flow; } public void setUp_flow(long up_flow) { this.up_flow = up_flow; } public long getD_flow() { return d_flow; } public void setD_flow(long d_flow) { this.d_flow = d_flow; } public long getS_flow() { return s_flow; } public void setS_flow(long s_flow) { this.s_flow = s_flow; } //将对象数据序列化到流中 @Override public void write(DataOutput out) throws IOException { out.writeUTF(phoneNB); out.writeLong(up_flow); out.writeLong(d_flow); out.writeLong(s_flow); } //从数据流中反序列出对象的数据 //从数据流中读出对象字段时，必须跟序列化时的顺序保持一致 @Override public void readFields(DataInput in) throws IOException { phoneNB = in.readUTF(); up_flow = in.readLong(); d_flow = in.readLong(); s_flow = in.readLong(); } @Override public String toString() { return "" + up_flow + "\t" +d_flow + "\t" + s_flow; } @Override public int compareTo(FlowBean o) { return s_flow>o.getS_flow()?-1:1; } }
TopkURLMapper.java：
package cn.itcast.hadoop.mr.llyy.topkurl; import java.io.IOException; import org.apache.commons.lang.StringUtils; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Mapper; import cn.itcast.hadoop.mr.flowsum.FlowBean; public class TopkURLMapper extends Mapper<LongWritable, Text, Text, FlowBean> { private FlowBean bean = new FlowBean(); private Text k = new Text(); @Override protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException { String line = value.toString(); String[] fields = StringUtils.split(line, "\t"); try { if (fields.length > 32 && StringUtils.isNotEmpty(fields[26]) && fields[26].startsWith("http")) { String url = fields[26]; long up_flow = Long.parseLong(fields[30]); long d_flow = Long.parseLong(fields[31]); k.set(url); bean.set("", up_flow, d_flow); context.write(k, bean); } } catch (Exception e) { System.out.println(); } } }
TopkURLReducer.java：
package cn.itcast.hadoop.mr.llyy.topkurl; import java.io.IOException; import java.util.Map.Entry; import java.util.Set; import java.util.TreeMap; import org.apache.hadoop.hdfs.server.namenode.HostFileManager.EntrySet; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Reducer; import cn.itcast.hadoop.mr.flowsum.FlowBean; public class TopkURLReducer extends Reducer<Text, FlowBean, Text, LongWritable>{ private TreeMap<FlowBean,Text> treeMap = new TreeMap<>(); private double globalCount = 0; // <url,{bean,bean,bean,.......}> @Override protected void reduce(Text key, Iterable<FlowBean> values,Context context) throws IOException, InterruptedException { Text url = new Text(key.toString()); long up_sum = 0; long d_sum = 0; for(FlowBean bean : values){ up_sum += bean.getUp_flow(); d_sum += bean.getD_flow(); } FlowBean bean = new FlowBean("", up_sum, d_sum); //每求得一条url的总流量，就累加到全局流量计数器中，等所有的记录处理完成后，globalCount中的值就是全局的流量总和 globalCount += bean.getS_flow(); treeMap.put(bean,url); } //cleanup方法是在reduer任务即将退出时被调用一次 @Override protected void cleanup(Context context) throws IOException, InterruptedException { Set<Entry<FlowBean, Text>> entrySet = treeMap.entrySet(); double tempCount = 0; for(Entry<FlowBean, Text> ent: entrySet){ if(tempCount / globalCount < 0.8){ context.write(ent.getValue(), new LongWritable(ent.getKey().getS_flow())); tempCount += ent.getKey().getS_flow(); }else{ return; } } } }
TopkURLRunner.java：
package cn.itcast.hadoop.mr.llyy.topkurl; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.conf.Configured; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; import org.apache.hadoop.util.Tool; import org.apache.hadoop.util.ToolRunner; import cn.itcast.hadoop.mr.flowsum.FlowBean; public class TopkURLRunner extends Configured implements Tool{ @Override public int run(String[] args) throws Exception { Configuration conf = new Configuration(); Job job = Job.getInstance(conf); job.setJarByClass(TopkURLRunner.class); job.setMapperClass(TopkURLMapper.class); job.setReducerClass(TopkURLReducer.class); job.setMapOutputKeyClass(Text.class); job.setMapOutputValueClass(FlowBean.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(LongWritable.class); FileInputFormat.setInputPaths(job, new Path(args[0])); FileOutputFormat.setOutputPath(job, new Path(args[1])); return job.waitForCompletion(true)?0:1; } public static void main(String[] args) throws Exception { int res = ToolRunner.run(new Configuration(), new TopkURLRunner(), args); System.exit(res); } }
将上面的运行结果通过sqoop导入到数据库中，然后通过数据库读取再跑mapreduce程序。
DBLoader.java：数据库的工具类。
package cn.itcast.hadoop.mr.llyy.enhance; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.Statement; import java.util.HashMap; public class DBLoader { public static void dbLoader(HashMap<String, String> ruleMap) { Connection conn = null; Statement st = null; ResultSet res = null; try { Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection("jdbc:mysql://weekend01:3306/urlcontentanalyse", "root", "root"); st = conn.createStatement(); res = st.executeQuery("select url,info from urlrule"); while (res.next()) { ruleMap.put(res.getString(1), res.getString(2)); } } catch (Exception e) { e.printStackTrace(); } finally { try{ if(res!=null){ res.close(); } if(st!=null){ st.close(); } if(conn!=null){ conn.close(); } }catch(Exception e){ e.printStackTrace(); } } } public static void main(String[] args) { DBLoader db = new DBLoader(); HashMap<String, String> map = new HashMap<String,String>(); db.dbLoader(map); System.out.println(map.size()); } }
LogEnhanceOutputFormat.java：默认是TextOutputFormat，这里我需要实现将不同的结果输到不同的文件中，而不是_SUCCESS中，所以我需要重写一个format。
package cn.itcast.hadoop.mr.llyy.enhance; import java.io.IOException; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FSDataOutputStream; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.mapreduce.RecordWriter; import org.apache.hadoop.mapreduce.TaskAttemptContext; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; public class LogEnhanceOutputFormat<K, V> extends FileOutputFormat<K, V> { @Override public RecordWriter<K, V> getRecordWriter(TaskAttemptContext job) throws IOException, InterruptedException { FileSystem fs = FileSystem.get(new Configuration()); FSDataOutputStream enhancedOs = fs.create(new Path("/liuliang/output/enhancedLog")); FSDataOutputStream tocrawlOs = fs.create(new Path("/liuliang/output/tocrawl")); return new LogEnhanceRecordWriter<K, V>(enhancedOs,tocrawlOs); } public static class LogEnhanceRecordWriter<K, V> extends RecordWriter<K, V>{ private FSDataOutputStream enhancedOs =null; private FSDataOutputStream tocrawlOs =null; public LogEnhanceRecordWriter(FSDataOutputStream enhancedOs,FSDataOutputStream tocrawlOs){ this.enhancedOs = enhancedOs; this.tocrawlOs = tocrawlOs; } @Override public void write(K key, V value) throws IOException, InterruptedException { if(key.toString().contains("tocrawl")){ tocrawlOs.write(key.toString().getBytes()); }else{ enhancedOs.write(key.toString().getBytes()); } } @Override public void close(TaskAttemptContext context) throws IOException, InterruptedException { if(enhancedOs != null){ enhancedOs.close(); } if(tocrawlOs != null){ tocrawlOs.close(); } } } }
LogEnhanceMapper.java：
package cn.itcast.hadoop.mr.llyy.enhance; import java.io.IOException; import java.util.HashMap; import org.apache.commons.lang.StringUtils; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.NullWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Mapper; /** * * * 读入原始日志数据，抽取其中的url，查询规则库，获得该url指向的网页内容的分析结果，追加到原始日志后 * * @author [email protected] * */ // 读入原始数据 （47个字段） 时间戳 ..... destip srcip ... url .. . get 200 ... // 抽取其中的url查询规则库得到众多的内容识别信息 网站类别，频道类别，主题词，关键词，影片名，主演，导演。。。。 // 将分析结果追加到原始日志后面 // context.write( 时间戳 ..... destip srcip ... url .. . get 200 ... // 网站类别，频道类别，主题词，关键词，影片名，主演，导演。。。。) // 如果某条url在规则库中查不到结果，则输出到带爬清单 // context.write( url tocrawl) public class LogEnhanceMapper extends Mapper<LongWritable, Text, Text, NullWritable> { private HashMap<String, String> ruleMap = new HashMap<>(); // setup方法是在mapper task 初始化时被调用一次 @Override protected void setup(Context context) throws IOException, InterruptedException { DBLoader.dbLoader(ruleMap); } @Override protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException { String line = value.toString(); String[] fields = StringUtils.split(line, "\t"); try { if (fields.length > 27 && StringUtils.isNotEmpty(fields[26]) && fields[26].startsWith("http")) { String url = fields[26]; String info = ruleMap.get(url); String result = ""; if (info != null) { result = line + "\t" + info + "\n\r"; context.write(new Text(result), NullWritable.get()); } else { result = url + "\t" + "tocrawl" + "\n\r"; context.write(new Text(result), NullWritable.get()); } } else { return; } } catch (Exception e) { System.out.println("exception occured in mapper....."); } } }
LogEnhanceRunner.java：
package cn.itcast.hadoop.mr.llyy.enhance; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.conf.Configured; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.NullWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; import org.apache.hadoop.util.Tool; import org.apache.hadoop.util.ToolRunner; public class LogEnhanceRunner extends Configured implements Tool{ @Override public int run(String[] args) throws Exception { Configuration conf = new Configuration(); Job job = Job.getInstance(conf); job.setJarByClass(LogEnhanceRunner.class); job.setMapperClass(LogEnhanceMapper.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(NullWritable.class); job.setOutputFormatClass(LogEnhanceOutputFormat.class); FileInputFormat.setInputPaths(job, new Path(args[0])); FileOutputFormat.setOutputPath(job, new Path(args[1])); return job.waitForCompletion(true)?0:1; } public static void main(String[] args) throws Exception { int res = ToolRunner.run(new Configuration(), new LogEnhanceRunner(),args); System.exit(res); } }
这里不写reduce也行。
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