Java Top 100熱門問答(Stackoverflow)

• Java += 操做符實質

• 將InputStream轉換爲String

• 將數組轉換爲List

• 如何遍歷map對象

• public，protected，private，不加修飾符。有什麼區別呢？

• 如何測試一個數組是否包含指定的值？

• 重寫（Override）equlas和hashCode方法時應考慮的問題

• 從一個多層嵌套循環中直接跳出

• 如何將String轉換爲Int

• 如何分割（split）string字符串

• 在java中如何對比（compare）string

• Map<Key,Value>基於Value值排序

• `HashMap和Hashtable的區別

• 如何便捷地將兩個數組合到一塊兒

• Java 是否支持默認的參數值

• Java 產生指定範圍的隨機數

• JavaBean 究竟是什麼

• wait()和sleep()的區別

• 可否在一個構造器( constructor )中調用另外一個構造器

• finally 代碼塊總會被執行麼

• 如何將String轉換爲enum

• 在Java中聲明數組

• 反射是什麼及其用途

• 爲何不能用string類型進行switch判斷

• 比較java枚舉成員使用equal仍是==

• 用java怎麼建立一個文件並向該文件寫文本內容

• serialVersionUID 有什麼做用？該如何使用？

編程技巧

• 去掉煩人的「!=null」(判空語句

• 獲取完整的堆棧信息

• 如何用一行代碼初始化一個ArrayList

• 初始化靜態map

• 給3個布爾變量，當其中有2個或者2個以上爲true才返回true

• 輸出 Java 數組最簡單的方式

• 爲何如下用隨機生成的文字會得出 「hello world」?

• 什麼在java中存放密碼更傾向於char[]而不是String

• 如何避免在JSP文件中使用Java代碼

• Java 源碼裏的設計模式

• 如何產生一個隨機的字母數字串做爲 session 的惟一標識符

• 如何建立單例

• 實現Runnable接口 VS. 繼承Thread類

• 我應該用哪個@NotNull註解

• 怎樣將堆棧追蹤信息轉換爲字符串

• 如何處理 java.lang.outOfMemoryError PermGen space error

網絡

• 如何使用java.net.URLConnection接收及發送HTTP請求

性能

• LinkedList、ArrayList各自的使用場景，如何確認應該用哪個呢？

• StringBuilder和StringBuffer有哪些區別呢

• 爲何處理排序的數組要比非排序的快

測試

• 如何測試 private 方法，變量或者內部類

Android

• 在Android裏面下載文件，並在ProgressDialog顯示進度

• 如何獲取Android設備惟一ID

待翻譯問題連接(還剩x問題)

• Why is subtracting these two times (in 1927) giving a strange result?

• Proper use cases for Android UserManager.isUserAGoat()?

• Creating a memory leak with Java [closed] 用戶AutumnLight正在翻譯該問題

• Why is printing 「B」 dramatically slower than printing 「#」?

• How can I create an executable jar with dependencies using Maven?

• Why is executing Java code in comments with certain Unicode characters allowed?

• Convert a String to an enum in Java

• Android SDK installation doesn’t find JDK

• Java inner class and static nested class

• ‘Must Override a Superclass Method’ Errors after importing a project into Eclipse

• Fastest way to determine if an integer’s square root is an integer

• How to fix: Unsupported major.minor version 51.0 error?

• How to generate a random alpha-numeric string?

• Comparing Java enum members: == or equals()?

• Failed to load the JNI shared Library (JDK)

• How to create a Java String from the contents of a file?

• How do you assert that a certain exception is thrown in JUnit 4 tests?

• What exactly is Apache Camel?

• How can I permanently have line numbers in IntelliJ?

• How do servlets work? Instantiation, shared variables and multithreading

• Access restriction on class due to restriction on required library rt.jar?

• How do I discover memory usage of my application in Android?

• How can I generate an MD5 hash?

• Uncatchable ChuckNorrisException

• Can I add jars to maven 2 build classpath without installing them?

• Update Eclipse with Android development tools v. 23

• Setting multiple jars in java classpath

• Iterating through a list, avoiding ConcurrentModificationException when removing in loop

• Is null check needed before calling instanceof

• How does the Java for each loop work?

• What is the Java equivalent for LINQ?

• Hibernate hbm2ddl.auto possible values and what they do?

• How to round a number to n decimal places in Java

• How can I pad an integers with zeros on the left?

• Sort ArrayList of custom Objects by property

• What’s the difference between @Component, @Repository & @Service annotations in Spring?

• Why is Java Vector class considered obsolete or deprecated?

• Efficiency of Java 「Double Brace Initialization」?

• Why does this go into an infinite loop?

• When and how should I use a ThreadLocal variable?

• decompiling DEX into Java sourcecode

• How to create a generic array in Java?

• Why does Math.round(0.49999999999999994) return 1

• Eclipse: Set maximum line length for auto formatting?

• What is the difference between a soft reference and a weak reference in Java?

• What is the equivalent of the C++ Pair in Java?

• What is the difference between JSF, Servlet and JSP?

• How do I 「decompile」 Java class files?

• Useful Eclipse Java Code Templates [closed]

• How to call SOAP web service in Android

原文：http://www.cricode.com/4182.html