在方法内部定义的内部类不能访问方法的局部变量,除非标记了这些局部变量.我已经final查看了堆栈溢出和java代码牧场中的其他帖子,但它们似乎都没有完全回答关于如何标记的问题变量final允许内部类访问方法中的局部变量.
class MyOuter {
private String x = "Outer";
void fly(final int speed) {
final int e = 1;
class FlyingEquation {
public void seeOuter()
{
System.out.println("Outer x is " + x);
}
public void display()
{
System.out.println(e);// line 1
System.out.println(speed);// line 2
}
}
FlyingEquation f=new FlyingEquation();
f.seeOuter();
f.display();
}
public static void main(String args[])
{
MyOuter mo=new MyOuter();
mo.fly(5);
}
}
我发现的解释:
局部变量存储在堆栈中,一旦方法调用完成,就会弹出堆栈并且局部变量不可访问,而 最终局部变量存储在内存的数据部分中,JVM即使在方法调用结束后也可能允许访问它们.在哪里data …
我有一个学生表,其中包含以下字段:
student(student_id, student_name, student_avg)
我需要在MySQL中编写一个查询,将结果显示为:
序列号.=>结果还应该有一个带有序列号的新列,1,2,3,...,n就像结果中每行的自动增量一样.
student_id
student_name
student_avg > 4
我不想以任何方式改变我的桌子.我所要做的就是写一个查询,它会给我上面的结果.我希望我很清楚.
示例数据:
student_id student_name student_avg
1 abc 2.5
2 xyz 4.1
3 def 4.2
查询后的示例输出:
serial_no student_id student_name student_avg
1 2 xyz 4.1
2 3 def 4.2
这是我正在使用的json对象
{
"name": "John Smith",
"age": 32,
"employed": true,
"address": {
"street": "701 First Ave.",
"city": "Sunnyvale, CA 95125",
"country": "United States"
},
"children": [
{
"name": "Richard",
"age": 7
},
{
"name": "Susan",
"age": 4
},
{
"name": "James",
"age": 3
}
]
}
我希望这是另一个键值对:
"collegeId": {
"eventno": "6062",
"eventdesc": "abc"
};
我尝试了concat,但这给了我||的结果 符号和我cdnt迭代.我使用溢出,但只删除逗号.
concattedjson = JSON.stringify(JSON.parse(json1).concat(JSON.parse(json2)));
如何将键对值添加到现有的json对象？我在javascript工作.
除此之外字节通过消耗只有八个存储位作为对节约了内存的事实，32位的integer。它还有哪些实际用途？我在一篇文章中读到，当我们处理来自网络或文件的数据流时，它很有用。当您处理可能与 Java 的其他内置类型不直接兼容的原始二进制数据时，它们也很有用。任何人都可以用例子来解释这些吗？并说明一些更实际的用途？
首先,我检查了有关此问题的讨论,但无法找到我的问题的答案,这就是我打开这个问题的原因.
我使用restlet 2.0.15设置了一个Web服务.该实现仅适用于服务器.与服务器的连接是通过网页进行的,因此我没有使用ClientResource.
用尽线程池问题的大部分答案都表明包含了
#exhaust + #release
Web服务的过程可以描述为单个函数.GET从网页接收请求,查询数据库,以XML格式化结果并返回最终表示.我使用Filter来覆盖beforeHandle和afterHandle.
组件创建代码的代码:
Component component = new Component();
component.getServers().add(Protocol.HTTP, 8188);
component.getContext().getParameters().add("maxThreads", "512");
component.getContext().getParameters().add("minThreads", "100");
component.getContext().getParameters().add("lowThreads", "145");
component.getContext().getParameters().add("maxQueued", "100");
component.getContext().getParameters().add("maxTotalConnections", "100");
component.getContext().getParameters().add("maxIoIdleTimeMs", "100");
component.getDefaultHost().attach("/orcamento2013", new ServerApp());
component.start();
这些参数是本论坛中讨论的结果,也是我本人为了最大限度地提高效率而进行修改的结果.
来到应用程序,代码如下:
@Override
public synchronized Restlet createInboundRoot() {
// Create a router Restlet that routes each call to a
// new instance of HelloWorldResource.
Router router = new Router(getContext());
// Defines only one route
router.attach("/{taxes}", ServerImpl.class);
//router.attach("/acores/{taxes}", ServerImplAcores.class);
System.out.println(router.getRoutes().size());
OriginFilter originFilter = new OriginFilter(getContext());
originFilter.setNext(router);
return …这是我写的程序:
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package javaapplication1;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.StringTokenizer;
import net.sf.json.JSONException;
import net.sf.json.JSONObject;
/**
*
* @author 311001
*/
public class NewClass {
public static void main(String args[]) {
JSONObject parentData = new JSONObject();
JSONObject childData = new JSONObject();
try {
parentData.put("command", "login");
parentData.put("uid", "123123123");
childData.put("uid", "007");
childData.put("username", "sup");
childData.put("password", "bros");
parentData.put("params", childData);
System.out.println(parentData);
Map<String, String> map …我是Ruby的新手,无法弄清楚如何从用户那里获取数组的输入并显示它.如果有人能够清楚我可以添加我的逻辑来找到最大的数字.
#!/usr/bin/ruby
puts "Enter the size of the array"
n = gets.chomp.to_i
puts "enter the array elements"
variable1=Array.new(n)
for i in (0..n)
variable1[i]=gets.chomp.to_i
end
for i in (0..n)
puts variable1
end
java.net.SocketException: Connection reset by peer: socket write error
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(Unknown Source)
at java.net.SocketOutputStream.write(Unknown Source)
at java.io.DataOutputStream.write(Unknown Source)
at java.io.DataOutputStream.writeUTF(Unknown Source)
at java.io.DataOutputStream.writeUTF(Unknown Source)
at SignUp.setUser(SignUp.java:225)
at SignUp.jButton1_actionPerformed(SignUp.java:207)
at SignUp.access$3(SignUp.java:201)
at SignUp$4.actionPerformed(SignUp.java:135)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at …