The Italian economy, for example, is no longer cruising in Germany’s slipsteam.

“Italy used to produce a lot of goods that would feed the German industrial machine,” said Jens Sondergaard, an economist at Nomura in London. But much of that German business is going to Eastern Europe or elsewhere, where costs are lower and companies are increasingly able to match Italian quality. Indeed, despite the strong German economy, Italian exports to Germany were €3.2 billion lower in 2010 than in 2008.

“That is bad news for Italy,” Mr. Sondergaard said.

Where Germany puts its money is crucial to the 17-nation euro zone economy. Germany accounts for nearly a third of the euro area’s exports. Germany has a trade surplus so far this year, while France, Italy, Spain and the region as a whole have large deficits.

With decades of European economic integration under their belt, German companies still exported much more to France last year than to China — €91 billion compared with €54 billion.

But the gap is closing fast. Exports to China rose 44 percent in 2010 compared with a 12 percent increase for France. Mr. Wen, the prime minister, predicted during his visit to Berlin last month that trade with Germany would double within five years.

Moreover, in 2009, German manufacturers for the first time invested more in China — €11.6 billion, a 50 percent increase from 2006 — than they did in France, which, along with Italy and Spain, is drawing markedly less German industrial investment than a few years ago.

This profound shift is visible at the Trumpf factory complex in Ditzingen, near Stuttgart. Not long ago, Trumpf was considered part of the Mittelstand, the midsize, family-owned engineering companies that power the German economy. But these days, Trumpf is a global powerhouse.

From humble prewar beginnings, Trumpf, a maker of machines that use lasers to work metal, has grown to the point where it now employs about 2,000 people in Ditzingen and 6,000 at other locations around the world. That is not counting the robotic lawnmower prowling outside the executive office building — a sign of the scarcity of labor in southwestern Germany, where unemployment is less than 5 percent.