1.javaä¸å¸¸è§çå¼å¸¸ç±»
2.throwableåExceptionçåºå«(详ç»ä¸ç¹)
3.exception和error区别
4.javaä¸ å¼å¸¸ç±»Exception(String message, Throwable cause)
5.exceptionåerrorçåºå«
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Javaè¯è¨è¦æ±javaç¨åºä¸ï¼æ 论æ¯è°åç代ç ï¼æææåºï¼throwï¼çå¼å¸¸é½å¿ é¡»æ¯ä»Throwableæ´¾çèæ¥ãå½ç¶ï¼å®é çJavaç¼ç¨ä¸ï¼ç±äºJDKå¹³å°å·²ç»ä¸ºæ们设计好äºé常丰å¯åå®æ´çå¼å¸¸å¯¹è±¡å类模åãå æ¤ï¼javaç¨åºåä¸è¬æ¯ä¸éè¦åéæ°å®ä¹èªå·±çå¼å¸¸å¯¹è±¡ãèä¸å³ä¾¿æ¯éè¦æ©å±èªå®ä¹çå¼å¸¸å¯¹è±¡ï¼ä¹å¾å¾ä¼ä»Exceptionæ´¾çèæ¥ãæ以ï¼å¯¹äºjavaç¨åºåèè¨ï¼å®ä¸è¬åªéè¦å¨å®ç顶级å½æ°ä¸catch(Exception ex)å°±å¯ä»¥æè·åºææçå¼å¸¸å¯¹è±¡ã ææå¼å¸¸å¯¹è±¡çæ ¹åºç±»æ¯ Throwable ï¼Throwableä»Objectç´æ¥ç»§æ¿èæ¥ï¼è¿æ¯javaç³»ç»æ强å¶è¦æ±çï¼ï¼å¹¶ä¸å®å®ç°äº Serializableæ¥å£ï¼è¿ä¸ºææçå¼å¸¸å¯¹è±¡é½è½å¤è½»æ¾è·¨è¶Javaç»ä»¶ç³»ç»å好äºæå åçç©è´¨åå¤ï¼ãä»Throwableç´æ¥æ´¾çåºçå¼å¸¸ç±»æExceptionåError ãExceptionæ¯javaç¨åºåææçæçï¼å®ä¸è¬ä»£è¡¨äºçæ£å®é æä¹ä¸çå¼å¸¸å¯¹è±¡çæ ¹åºç±»ãä¹å³æ¯è¯´ï¼ Exception åä»å®æ´¾çèæ¥çææå¼å¸¸é½æ¯åºç¨ç¨åºè½å¤catchå°çï¼å¹¶ä¸å¯ä»¥è¿è¡å¼å¸¸é误æ¢å¤å¤ççå¼å¸¸ç±»åãèErrorå表示Javaç³»ç»ä¸åºç°äºä¸ä¸ªé常严éçå¼å¸¸é误ï¼å¹¶ä¸è¿ä¸ªé误å¯è½æ¯åºç¨ç¨åºæä¸è½æ¢å¤çï¼ä¾å¦LinkageError ï¼æ ThreadDeath çã
exception和error区别
以java为例,其exception和error的区别如下:
1、Exception和Error都继承了Throwable类,在java中只有Throwable类型的燕窝溯源码025实例才可以被抛出(Throw)或者捕捉(catch),它是异常处理机制的基本组成类型。Exception是电影开场粒子源码程序正常运行中,可以预料的意外情况,可能并且应该被捕获,进行相应的处理。
2、Error指在正常情况下,不大可能出现的情况,绝大部门的负61的源码Error都会导致程序处于非正常的,不可恢复状态。既然是非正常情况,所以不便于也不需要捕获。内蒙麻将游戏源码比如常见的OutOfMemoryError之类,都是Error的子类。
Exception类又分为可检查异常(checked)和不检查异常(unchecked),ubbo原理和源码可检查异常在源码里必须显示的进行捕获处理,这是编译期检查的一部分。不检查异常就是所谓的运行时异常,类似NullPointerException,ArrayIndexOutOfBoundsException之类,通常是可以编码避免的逻辑错误。
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exceptionåerrorçåºå«
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2.Exception å Error ä½ç°äº Java å¹³å°è®¾è®¡è 对ä¸åå¼å¸¸æ åµçåç±»ãException æ¯ç¨åºæ£å¸¸è¿è¡ä¸ï¼å¯ä»¥é¢æçæå¤æ åµï¼å¯è½å¹¶ä¸åºè¯¥è¢«æè·ï¼è¿è¡ç¸åºå¤çã
3.Error æ¯æå¨æ£å¸¸æ åµä¸ï¼ä¸å¤§å¯è½åºç°çæ åµï¼ç»å¤§é¨åç Error é½ä¼å¯¼è´ç¨åºï¼æ¯å¦ JVM èªèº«ï¼å¤äºéæ£å¸¸çãä¸å¯æ¢å¤ç¶æãæ¢ç¶æ¯éæ£å¸¸æ åµï¼æ以ä¸ä¾¿äºä¹ä¸éè¦æè·ï¼å¸¸è§çæ¯å¦ OutOfMemoryError ä¹ç±»ï¼é½æ¯ Error çåç±»ã
4.Exception åå为å¯æ£æ¥ï¼checkedï¼å¼å¸¸åä¸æ£æ¥ï¼uncheckedï¼å¼å¸¸ï¼å¯æ£æ¥å¼å¸¸å¨æºä»£ç éå¿ é¡»æ¾å¼å°è¿è¡æè·å¤çï¼è¿æ¯ç¼è¯ææ£æ¥çä¸é¨åãåé¢æä»ç»çä¸å¯æ¥ç Errorï¼æ¯ Throwable ä¸æ¯ Exceptionã
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public static void main(String[] args) {
try (BufferedReader br = new BufferedReader(new FileReader("a"));
BufferedWriter writer = new BufferedWriter(new FileWriter("a"))) {
// Try-with-resources
} catch (IOException e) { // Multiple catch
// Handle it
}
}
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public static void main(String[] args) { try {
BufferedReader br = new BufferedReader(new FileReader("a"));
Throwable var2 = null; try {
BufferedWriter writer = new BufferedWriter(new FileWriter("a"));
Object var4 = null; if (writer != null) { if (var4 != null) { try {
writer.close();
} catch (Throwable var) {
((Throwable)var4).addSuppressed(var);
}
} else {
writer.close();
}
}
} catch (Throwable var) {
var2 = var; throw var;
} finally { if (br != null) { if (var2 != null) { try {
br.close();
} catch (Throwable var) {
var2.addSuppressed(var);
}
} else {
br.close();
}
}
}
} catch (IOException var) {
}
}
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