获得;java.lang.ClassNotFoundException:org.json.simple.parser.ParseException“;将JSON对象作为映射器的输入值读取时
我编写了一个映射程序,打算读取JSON数据。代码如下所示:获得;java.lang.ClassNotFoundException:org.json.simple.parser.ParseException“;将JSON对象作为映射器的输入值读取时,java,json,hadoop,mapreduce,classnotfoundexception,Java,Json,Hadoop,Mapreduce,Classnotfoundexception,我编写了一个映射程序,打算读取JSON数据。代码如下所示: public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException { System.out.println("Into Map"); try { String line = value.toString(); JSONParser j
public void map(LongWritable key, Text value, Context context)
throws IOException, InterruptedException {
System.out.println("Into Map");
try {
String line = value.toString();
JSONParser jsonParser = new JSONParser();
JSONObject jsonObject = new JSONObject();
jsonObject = (JSONObject) jsonParser.parse(line);
String content = (String) jsonObject.get("content");
System.out.println(content);
StringTokenizer tokenizer = new StringTokenizer(content);
while (tokenizer.hasMoreTokens()) {
word.set(tokenizer.nextToken());
String strword = word.toString();
context.write(word, one);
}
} catch (ParseException ex) {
ex.printStackTrace();
}
}
但是,,
当我尝试运行映射程序时,
我发现以下错误:
Error: java.lang.ClassNotFoundException: org.json.simple.parser.ParseException
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:249)
at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:810)
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:855)
at org.apache.hadoop.mapreduce.JobContext.getMapperClass(JobContext.java:199)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:718)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:364)
at org.apache.hadoop.mapred.Child$4.run(Child.java:255)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1190)
at org.apache.hadoop.mapred.Child.main(Child.java:249)
有人能指出我做错了什么吗?这是个小错误。
我没有把jar放在hadoop/lib文件夹中。我只把它们放在eclipse工作区中
另外,我先是删除了这篇文章,但后来我看到其他人在另一个论坛上问了类似的问题。因此,我取消了问题并回答了它。此外,我还对问题进行了编辑,以突出实际原因