finally瀛愬彞
JVM鎵цJava瀛楄妭鐮佹椂錛屽畠鏈夊嚑縐嶆柟寮忓彲浠ラ鍑轟竴涓唬鐮佸潡錛堣姳鎷彿涓棿鐨勮鍙ワ級銆傚叾涓箣涓錛屽氨鏄畝鍗曠殑鎵ц瀹屽叾涓墍鏈夌殑璇彞錛岀劧鍚庨鍑轟唬鐮佸潡銆傜浜岀錛孞VM鍙兘浼氬湪浠ｇ爜鍧椾腑闂寸殑浠諱綍涓澶勶紝閬囧埌鍍廱reak錛宑ontinue錛宺eturn涔嬬被鐨勮鍙ワ紝寮哄埗瀹冭煩鍑鴻浠ｇ爜鍧椼傜涓夌錛孞VM鍙兘浼氬湪鎵ц榪囩▼涓紝鍑虹幇浜嗗紓甯革紝鐒跺悗瀹冭煩杞埌鍖歸厤鐨刢atch瀛愬彞錛屾垨鑰呮病鏈夋壘鍒扮浉搴旂殑catch瀛愬彞錛岀洿鎺ラ鍑哄綋鍓嶇嚎紼嬨傜敱浜庡崟涓唬鐮佸潡鏈夊姝ゅ鐨勬綔鍦ㄩ鍑虹偣錛坋xit point錛夛紝鎷ユ湁涓涓畝鍗曠殑鏂瑰紡鏉ヨ〃杈鋸滄棤璁轟唬鐮佸潡浠ヤ粈涔堟柟寮忛鍑猴紝鏈変簺浜嬫儏鎬昏兘鍙戠敓鈥濇槸寰堝煎緱鐨勩傜劧鍚庡氨鏈変簡try-finally瀛愬彞銆?nbsp; 闃呰鍏ㄦ枃
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寮傚父澶勭悊
鍦ㄧ▼搴忚繍琛屾椂錛屽紓甯歌浣犲彲浠ュ鉤婊戠殑澶勭悊鎰忓鐘跺喌銆備負浜嗘紨紺篔VM澶勭悊寮傚父鐨勬柟寮忥紝鑰冭檻NitPickyMath綾伙紝瀹冩彁渚涘鏁存暟榪涜鍔狅紝鍑忥紝涔橈紝闄や互鍙婂彇浣欑殑鎿嶄綔銆?br />
NitPickyMath鎻愪緵鐨勮繖浜涙搷浣滃拰Java璇█鐨?#8220;+”錛?#8220;-”錛?#8220;*”錛?#8220;/”鍜?#8220;%”鏄竴鏍風殑錛岄櫎浜哊itPickyMath涓殑鏂規硶鍦ㄤ互涓嬫儏鍐典笅浼氭姏鍑烘鏌ュ瀷錛坈hecked錛夊紓甯革細涓婃孩鍑猴紝涓嬫孩鍑轟互鍙婅0闄ゃ?鍋氶櫎鏁版椂錛孞VM浼氭姏鍑篈rithmeticException寮傚父錛屼絾鏄笂婧㈠嚭鍜屼笅婧㈠嚭涓嶄細寮曞彂浠諱綍寮傚父銆侼itPickyMath涓姏鍑哄紓甯哥殑鏂規硶瀹氫箟濡備笅錛?/p>
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class OverflowException extends Exception {
-
}
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class UnderflowException extends Exception {
-
}
-
class DivideByZeroException extends Exception {
-
}
NitPickyMath綾諱腑鐨剅emainder()鏂規硶灝辨槸涓涓姏鍑哄拰鎹曡幏寮傚父鐨勭畝鍗曟柟娉曘?/p>
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static int remainder(int dividend, int divisor)
-
throws DivideByZeroException {
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try {
-
return dividend % divisor;
-
}
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catch (ArithmeticException e) {
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throw new DivideByZeroException();
-
}
-
}
remainder()鏂規硶錛屽彧鏄畝鍗曠殑瀵瑰綋浣滃弬鏁頒紶閫掕繘鏉ョ殑2涓暣鏁拌繘琛屽彇浣欐搷浣溿傚鏋滃彇浣欐搷浣滅殑闄ゆ暟鏄?錛屼細寮曞彂ArithmeticException寮傚父銆俽emainder()鏂規硶鎹曡幏榪欎釜寮傚父錛屽茍閲嶆柊鎶涘嚭DivideByZeroException寮傚父銆?/p>
DivideByZeroException鍜孉rithmeticException鐨勫尯鍒槸錛孌ivideByZeroException鏄鏌ュ瀷錛坈hecked錛夊紓甯革紝鑰孉rithmeticException鏄潪媯鏌ワ紙unchecked錛夊瀷寮傚父銆傜敱浜嶢rithmeticException鏄潪媯鏌ュ瀷寮傚父錛屼竴涓柟娉曞氨綆椾細鎶涘嚭璇ュ紓甯革紝涔熶笉蹇呭湪鍏秚hrow瀛愬彞涓０鏄庡畠銆備換浣旹rror鎴朢untimeException寮傚父鐨勫瓙綾誨紓甯擱兘鏄潪媯鏌ュ瀷寮傚父銆傦紙ArithmeticException灝辨槸RuntimeException鐨勫瓙綾匯傦級閫氳繃鎹曡幏ArithmeticException鍜屾姏鍑篋ivideByZeroException錛宺emainder()鏂規硶寮鴻揩瀹冪殑璋冪敤鑰呭幓澶勭悊闄ゆ暟涓?鐨勫彲鑳芥э紝瑕佷箞鎹曡幏瀹冿紝瑕佷箞鍦ㄥ叾throw瀛愬彞涓０鏄嶥ivideByZeroException寮傚父銆傝繖鏄洜涓猴紝鍍廌ivideByZeroException榪欑鍦ㄦ柟娉曚腑鎶涘嚭鐨勬鏌ュ瀷寮傚父錛岃涔堝湪鏂規硶涓崟鑾鳳紝瑕佷箞鍦ㄥ叾throw瀛愬彞涓０鏄庯紝浜岃呭繀閫夊叾涓銆傝屽儚ArithmeticException榪欑闈炴鏌ュ瀷寮傚父錛屽氨涓嶉渶瑕佸幓鏄懼紡鎹曡幏鍜屽０鏄庛?/p>
javac涓簉emainder()鏂規硶鐢熸垚鐨勫瓧鑺傜爜搴忓垪濡備笅錛?/p>
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// The main bytecode sequence for remainder:
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0 iload_0 // Push local variable 0 (arg passed as divisor)
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1 iload_1 // Push local variable 1 (arg passed as dividend)
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2 irem // Pop divisor, pop dividend, push remainder
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3 ireturn // Return int on top of stack (the remainder)
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// The bytecode sequence for the catch (ArithmeticException) clause:
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4 pop // Pop the reference to the ArithmeticException
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// because it is not used by this catch clause.
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5 new #5 < Class DivideByZeroException >
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// Create and push reference to new object of class
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// DivideByZeroException.
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8 dup // Duplicate the reference to the new
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// object on the top of the stack because it
-
// must be both initialized
-
// and thrown. The initialization will consume
-
// the copy of the reference created by the dup.
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9 invokenonvirtual #9 < Method DivideByZeroException.< init >()V >
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// Call the constructor for the DivideByZeroException
-
// to initialize it. This instruction
-
// will pop the top reference to the object.
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12 athrow // Pop the reference to a Throwable object, in this
-
// case the DivideByZeroException,
-
// and throw the exception.
remainder()鏂規硶鐨勫瓧鑺傜爜鏈?涓崟鐙殑閮ㄥ垎銆傜涓閮ㄥ垎鏄鏂規硶鐨勬甯告墽琛岃礬寰勶紝榪欓儴鍒嗕粠絎?琛屽紑濮嬶紝鍒扮3琛岀粨鏉熴傜浜岄儴鍒嗘槸浠庣4琛屽紑濮嬶紝鍒?2琛岀粨鏉熺殑catch瀛愬彞銆?/p>
涓誨瓧鑺傜爜搴忓垪涓殑irem鎸囦護鍙兘浼氭姏鍑篈rithmeticException寮傚父銆傚鏋滃紓甯稿彂鐢熶簡錛孞VM閫氳繃鍦ㄥ紓甯歌〃涓煡鎵懼尮閰嶇殑寮傚父錛屽畠浼氱煡閬撹璺寵漿鍒扮浉搴旂殑寮傚父澶勭悊鐨刢atch瀛愬彞鐨勫瓧鑺傜爜搴忓垪閮ㄥ垎銆傛瘡涓崟鑾峰紓甯哥殑鏂規硶錛岄兘璺熺被鏂囦歡涓笌鏂規硶瀛楄妭鐮佷竴璧蜂氦浠樼殑寮傚父琛ㄥ叧鑱斻傛瘡涓涓崟鑾峰紓甯哥殑try鍧楋紝閮芥槸寮傚父琛ㄤ腑鐨勪竴琛屻傛瘡琛?鏉′俊鎭細寮濮嬭鍙鳳紙from錛夊拰緇撴潫琛屽彿錛坱o錛夛紝瑕佽煩杞殑瀛楄妭鐮佸簭鍒楄鍙鳳紙target錛夛紝琚崟鑾風殑寮傚父綾葷殑甯擱噺姹犵儲寮曪紙type錛夈俽emainder()鏂規硶鐨勫紓甯歌〃濡備笅鎵紺猴細
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FROM
|
TO
|
TARGET
|
TYPE
|
|---|---|---|---|
| 0 | 4 | 4 | < Class java.lang.ArithmeticException > |
涓婇潰鐨勫紓甯歌〃琛ㄦ槑錛岃鍙?鍒?鑼冨洿鍐咃紝ArithmeticException灝嗚鎹曡幏銆傚紓甯歌〃涓殑“to”涓嬮潰鐨勭粨鏉熻鍙峰緇堟瘮寮傚父鎹曡幏鐨勬渶澶ц鍙峰ぇ1錛屼笂琛ㄤ腑錛岀粨鏉熻鍙蜂負4錛岃屽紓甯告崟鑾風殑鏈澶ц鍙鋒槸3銆傝鍙?鍒?鐨勫瓧鑺傜爜搴忓垪瀵瑰簲remainder()鏂規硶涓殑try鍧椼?#8220;target”鍒椾腑錛屾槸琛?鍒?鐨勫瓧鑺傜爜鍙戠敓ArithmeticException寮傚父鏃惰璺寵漿鍒扮殑鐩爣琛屽彿銆?/p>
濡傛灉鏂規硶鎵ц榪囩▼涓駭鐢熶簡寮傚父錛孞VM浼氬湪寮傚父琛ㄤ腑鏌ユ壘鍖歸厤琛屻傚紓甯歌〃涓殑鍖歸厤琛岃絎﹀悎涓嬮潰鐨勬潯浠訛細褰撳墠pc瀵勫瓨鍣ㄧ殑鍊艱鍦ㄨ琛岀殑琛ㄧず鑼冨洿涔嬪唴錛孾from, to)錛屼笖浜х敓鐨勫紓甯告槸璇ヨ鎵鎸囧畾鐨勫紓甯哥被鎴栧叾瀛愮被銆侸VM鎸変粠涓婂埌涓嬬殑嬈″簭鏌ユ壘寮傚父琛ㄣ傚綋鎵懼埌浜嗙涓涓尮閰嶈錛孞VM鎶妏c瀵勫瓨鍣ㄨ涓烘柊鐨勮煩杞鍙鳳紝浠庢琛岀戶緇線涓嬫墽琛屻傚鏋滄壘涓嶅埌鍖歸厤琛岋紝JVM寮瑰嚭褰撳墠鏍堝撫錛屽茍閲嶆柊鎶涘嚭鍚屼竴涓紓甯搞傚綋JVM寮瑰嚭褰撳墠鏍堝撫鏃訛紝瀹冧細緇堟褰撳墠鏂規硶鐨勬墽琛岋紝榪斿洖鍒拌皟鐢ㄨ鏂規硶鐨勪笂涓涓柟娉曢偅閲屻傝繖鏃訛紝鍦ㄤ笂涓涓柟娉曢噷錛屽茍涓嶄細緇х畫姝ｅ父鐨勬墽琛岃繃紼嬶紝鑰屾槸鎶涘嚭鍚屾牱鐨勫紓甯革紝淇冧嬌JVM閲嶆柊鏌ユ壘璇ユ柟娉曠殑寮傚父琛ㄣ?/p>
Java紼嬪簭鍛樺彲浠ョ敤throw璇彞鎶涘嚭鍍弐emainder()鏂規硶鐨刢atch瀛愬彞涓殑寮傚父錛孌ivideByZeroException銆備笅琛ㄥ垪鍑轟簡鎶涘嚭寮傚父鐨勫瓧鑺傜爜錛?/p>
|
OPCODE
|
OPERAND(S)
|
DESCRIPTION
|
|---|---|---|
| athrow | (none) | pops Throwable object reference, throws the exception |
athrow鎸囦護鎶婃爤欏跺厓绱犲脊鍑猴紝璇ュ厓绱犲繀欏繪槸Throwable鐨勫瓙綾繪垨鍏惰嚜韜殑瀵硅薄寮曠敤錛岃屾姏鍑虹殑寮傚父綾誨瀷鐢辨爤欏跺脊鍑虹殑瀵硅薄寮曠敤鎵鎸囨槑銆?/p>
鏈枃璇戣嚜錛?a target="_blank" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; outline: none; color: #21759b;">How the Java virtual machine handles exceptions
鏈枃鍑鴻嚜錛?/strong>鐮佸啘鍚堜綔紺?/a> 銆?a style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; outline: none; color: #21759b;">JVM涓殑寮傚父澶勭悊錛岃漿杞借娉ㄦ槑銆?/p>
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