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1. ±à³Ì¹ßÀý(Programming Practices)
9.1 Ìṩ¶ÔʵÀýÒÔ¼°Àà±äÁ¿µÄ·ÃÎÊ¿ØÖÆ(Providing Access to Instance and Class Variables)
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9.2 ÒýÓÃÀà±äÁ¿ºÍÀà·½·¨(Referring to Class Variables and Methods)
±ÜÃâÓÃÒ»¸ö¶ÔÏó·ÃÎÊÒ»¸öÀàµÄ¾²Ì¬±äÁ¿ºÍ·½·¨¡£Ó¦¸ÃÓÃÀàÃûÌæ´ú¡£ÀýÈ磺
classMethod(); //OK
AClass.classMethod(); //OK
anObject.classMethod(); //AVOID!
9.3 ³£Á¿(Constants)
λÓÚforÑ»·ÖÐ×÷Ϊ¼ÆÊýÆ÷ÖµµÄÊý×Ö³£Á¿£¬³ýÁË-1,0ºÍ1Ö®Í⣬²»Ó¦±»Ö±½ÓдÈë´úÂë¡£
9.4 ±äÁ¿¸³Öµ(Variable Assignments)
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fooBar.fChar = barFoo.lchar = 'c'; // AVOID!
²»Òª½«¸³ÖµÔËËã·ûÓÃÔÚÈÝÒ×ÓëÏàµÈ¹ØÏµÔËËã·û»ìÏýµÄµØ·½¡£ÀýÈ磺
if (c++ = d++) { // AVOID! (Java disallows)
...
}
Ó¦¸Ãд³É
if ((c++ = d++) != 0) {
...
}
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d = (a = b + c) + r; // AVOID!
Ó¦¸Ãд³É
a = b + c;
d = a + r;
9.5 ÆäËü¹ßÀý(Miscellaneous Practices)
9.5.1 Ô²À¨ºÅ(Parentheses)
Ò»°ã¶øÑÔ£¬ÔÚº¬ÓжàÖÖÔËËã·ûµÄ±í´ïʽÖÐʹÓÃÔ²À¨ºÅÀ´±ÜÃâÔËËã·ûÓÅÏȼ¶ÎÊÌ⣬ÊǸöºÃ·½·¨¡£¼´Ê¹ÔËËã·ûµÄÓÅÏȼ¶¶ÔÄã¶øÑÔ¿ÉÄܺÜÇå³þ£¬µ«¶ÔÆäËûÈËδ±ØÈç´Ë¡£Äã²»ÄܼÙÉè±ðµÄ³ÌÐòÔ±ºÍÄãÒ»ÑùÇå³þÔËËã·ûµÄÓÅÏȼ¶¡£
if (a == b && c == d) // AVOID!
if ((a == b) && (c == d)) // RIGHT
9.5.2 ·µ»ØÖµ(Returning Values)
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if (booleanExpression) {
return true;
} else {
return false;
}
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return booleanExpression;
ÀàËÆµØ£º
if (condition) {
return x;
}
return y;
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return (condition ? x : y);
9.5.3 &
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package com.beckham.factory;
/**
* @author ×÷Õß<Beckham>
* Email:gaowm0207@gmail.com
* Jan 26, 2010 2:35:15 PM
* Version:1.0
*/
public interface Car {
public void start() ;
}
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