本文整理了Java中org.apache.flink.api.java.operators.UnsortedGrouping.minBy()方法的一些代码示例，展示了UnsortedGrouping.minBy()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。UnsortedGrouping.minBy()方法的具体详情如下：
包路径：org.apache.flink.api.java.operators.UnsortedGrouping
类名称：UnsortedGrouping
方法名：minBy

UnsortedGrouping.minBy介绍

[英]Applies a special case of a reduce transformation (minBy) on a grouped DataSet.

The transformation consecutively calls a ReduceFunctionuntil only a single element remains which is the result of the transformation. A ReduceFunction combines two elements into one new element of the same type.
[中]对分组数据集应用reduce转换（minBy）的特殊情况。
转换连续调用reduceFunction，直到只剩下一个元素，这是转换的结果。ReduceFunction将两个元素组合成一个相同类型的新元素。

代码示例

代码示例来源：origin: apache/flink

/**
 * This test validates that an InvalidProgramException is thrown when minBy
 * is used on a custom data type.
 */
@Test(expected = InvalidProgramException.class)
public void testCustomKeyFieldsGrouping() {
  final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
  this.customTypeData.add(new CustomType());
  UnsortedGrouping<CustomType> groupDs = env.fromCollection(customTypeData).groupBy(0);
  // should not work: groups on custom type
  groupDs.minBy(0);
}

代码示例来源：origin: apache/flink

/**
 * This test validates that an index which is out of bounds throws an
 * IndexOutOfBoundsException.
 */
@Test(expected = IndexOutOfBoundsException.class)
public void testOutOfTupleBoundsGrouping1() {
  final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
  UnsortedGrouping<Tuple5<Integer, Long, String, Long, Integer>> groupDs = env.fromCollection(emptyTupleData, tupleTypeInfo).groupBy(0);
  // should not work, key out of tuple bounds
  groupDs.minBy(5);
}

代码示例来源：origin: apache/flink

/**
 * This test validates that an index which is out of bounds throws an
 * IndexOutOfBoundsException.
 */
@Test(expected = IndexOutOfBoundsException.class)
public void testOutOfTupleBoundsGrouping2() {
  final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
  UnsortedGrouping<Tuple5<Integer, Long, String, Long, Integer>> groupDs = env.fromCollection(emptyTupleData, tupleTypeInfo).groupBy(0);
  // should not work, key out of tuple bounds
  groupDs.minBy(-1);
}

代码示例来源：origin: apache/flink

/**
 * This test validates that an index which is out of bounds throws an
 * IndexOutOfBoundsException.
 */
@Test(expected = IndexOutOfBoundsException.class)
public void testOutOfTupleBoundsGrouping3() {
  final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
  UnsortedGrouping<Tuple5<Integer, Long, String, Long, Integer>> groupDs = env.fromCollection(emptyTupleData, tupleTypeInfo).groupBy(0);
  // should not work, key out of tuple bounds
  groupDs.minBy(1, 2, 3, 4, -1);
}

代码示例来源：origin: apache/flink

/**
 * This test validates that no exceptions is thrown when an empty grouping
 * calls minBy().
 */
@Test
public void testMinByKeyFieldsGrouping() {
  final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
  UnsortedGrouping<Tuple5<Integer, Long, String, Long, Integer>> groupDs = env.fromCollection(emptyTupleData, tupleTypeInfo).groupBy(0);
  // should work
  try {
    groupDs.minBy(4, 0, 1, 2, 3);
  } catch (Exception e) {
    Assert.fail();
  }
}

代码示例来源：origin: apache/flink

private static DataSet<String> analyze(DataSet<String> input, DataSet<String> stats, int branches) {
    for (int i = 0; i < branches; i++) {
      final int ii = i;

      if (stats != null) {
        input = input.map(
          new RichMapFunction<String, String>() {
            @Override
            public String map(String value) {
              return value;
            }
        }).withBroadcastSet(stats.map(s -> "(" + s + ").map"), "stats");
      }

      DataSet<String> branch = input
        .map(s -> new Tuple2<>(0, s + ii)).returns(Types.TUPLE(Types.STRING, Types.INT))
        .groupBy(0)
        .minBy(1)
        .map(kv -> kv.f1).returns(Types.STRING);
      if (stats == null) {
        stats = branch;
      } else {
        stats = stats.union(branch);
      }
    }
    return stats.map(s -> "(" + s + ").stats");
  }
}