Winter Day39: Head first design patterns

When it comes to maintenance, in order to reuse (reuse) the purpose of use following the commitment, the outcome is not perfect.

Local modifications made to the code, the impact may be more than a local level.

The change will be removed and part of the package together, so that the other parts will not be affected. After the code changes, unexpected parts become scarce, the system becomes more flexible.

Design principles: identify applications may require changes in place, put them independent, and do not need to change the code of those mixed; for interface programming, rather than programming.

A part of the system changes will not affect other parts.

 

Could not stand feeling, examples can be understood, but a bit difficult to understand the implementation of the code,

Go learn some basic, then come back to learn design patterns.