@Override
	public boolean matches(Object item) {
		AbstractMetricSink metric = (AbstractMetricSink) item;
		Table table = (Table) metric.shell.executeCommand(metric.getDslName() + " list").getResult();
		return table != null && !CollectionUtils.isEmpty(table.getRows())
				&& table.getRows().contains(new TableRow().addValue(1, metric.getName()));
	}
A matcher that will assert that the {@code <metric type> list} shell command returns a list that contains the
expected metric.

@param <T> the type of metric sink fixture this is matching
@author Eric Bottard
@author Marius Bogoevici
spring-xd-shell/src/test/java/org/springframework/xd/shell/command/fixtures/MetricExistsMatcher.java