The Codeless Code: Case 18 Necessary Features
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This same monk of the Elephant’s Footprint was poring over
the code created by his clan. There were several competing
implementations of a particular Data Access Object; at
present he was attempting to decide which would become the
definitive one that his clan would adopt.
“Each implementation has its own particular virtues and
vexations,” said the monk to the Java master. “And each has
features the others lack. I must consign all but one to the
winds of oblivion. How am I to choose?”
“I cannot answer when I am thirsty,” said the master. “In
the cabinet beside you are three wooden cups. Fill one from
the river, the second from the temple well, and the third
from the water-seller in the village. Bring all back to me
without a drop spilled, and I will offer you what help I
can.”
The monk did this, and set all three vessels before the
master.
“What have you learned?” asked the master.
The monk bowed. “If you give a coin to the water-seller in
the village, he will strike a gong twice: once before
filling your cup, and again when you have had your first
sip. If you fill your cup from the temple well, no gong
sounds but the bucket is heavy. If you dip your cup in the
river, the fish are troubled and the river-god must be
appeased by a gift of ten white stones.”
“I can drink but one of these,” said the master. “Which will
I find the most pleasing?”
The monk considered carefully. “The river was cold, but not
altogether clear. The temple well I have drunk from in the
past: its waters are bitter with limestone. And though I am
not acquainted with the water-seller, I heard his gong many
times today. On this evidence, I would choose the cup from
the water-seller.”
“A most sensible conclusion,” said the master. “Indeed, I
have visited this same water-seller every morning for eight
years, and found the experience perfectly satisfying each
time. Which is the vessel that he filled?”
The master sipped from the indicated cup, and his face fell
in disappointment. “Young brother,” he said. “You have
completely misunderstood my thirst. Where is the sound of
the gong?”
