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courses:mapreduce-tutorial:step-27 [2012/01/28 18:46] straka |
courses:mapreduce-tutorial:step-27 [2012/01/28 18:58] straka |
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} | } | ||
</ | </ | ||
+ | Remark: If the '' | ||
Such implementation can be used as a type of //values//. If we wanted to use it as a type of //keys//, we need to implement [[http:// | Such implementation can be used as a type of //values//. If we wanted to use it as a type of //keys//, we need to implement [[http:// | ||
Line 55: | Line 56: | ||
===== PairWritable< | ===== PairWritable< | ||
- | As another example, we implement a type storing | + | As another example, we implement a type consisting of two user-defined '' |
+ | <code java> | ||
+ | public static class PairWritable< | ||
+ | private A first; | ||
+ | private B second; | ||
+ | |||
+ | public void readFields(DataInput in) throws IOException { | ||
+ | first.readFields(in); | ||
+ | second.readFields(in); | ||
+ | } | ||
+ | |||
+ | public void write(DataOutput out) throws IOException { | ||
+ | first.write(out); | ||
+ | second.write(out); | ||
+ | } | ||
+ | |||
+ | public A getFirst() { return first; } | ||
+ | public B getSecond() { return second; } | ||
+ | public void setFirst(A first) { this.first = first; } | ||
+ | public void setSecond(B first) { this.second = second; } | ||
+ | public PairWritable(A first, B second) { this.first = first; this.second = second; } | ||
+ | } | ||
+ | </ |