马府强
2 years ago
12 changed files with 420 additions and 0 deletions
@ -0,0 +1,8 @@ |
|||||
|
# Default ignored files |
||||
|
/shelf/ |
||||
|
/workspace.xml |
||||
|
# Datasource local storage ignored files |
||||
|
/../../../:\listdemo\.idea/dataSources/ |
||||
|
/dataSources.local.xml |
||||
|
# Editor-based HTTP Client requests |
||||
|
/httpRequests/ |
@ -0,0 +1,13 @@ |
|||||
|
<?xml version="1.0" encoding="UTF-8"?> |
||||
|
<project version="4"> |
||||
|
<component name="CompilerConfiguration"> |
||||
|
<annotationProcessing> |
||||
|
<profile name="Maven default annotation processors profile" enabled="true"> |
||||
|
<sourceOutputDir name="target/generated-sources/annotations" /> |
||||
|
<sourceTestOutputDir name="target/generated-test-sources/test-annotations" /> |
||||
|
<outputRelativeToContentRoot value="true" /> |
||||
|
<module name="listdemo" /> |
||||
|
</profile> |
||||
|
</annotationProcessing> |
||||
|
</component> |
||||
|
</project> |
@ -0,0 +1,20 @@ |
|||||
|
<?xml version="1.0" encoding="UTF-8"?> |
||||
|
<project version="4"> |
||||
|
<component name="RemoteRepositoriesConfiguration"> |
||||
|
<remote-repository> |
||||
|
<option name="id" value="central" /> |
||||
|
<option name="name" value="Central Repository" /> |
||||
|
<option name="url" value="https://repo.maven.apache.org/maven2" /> |
||||
|
</remote-repository> |
||||
|
<remote-repository> |
||||
|
<option name="id" value="central" /> |
||||
|
<option name="name" value="Maven Central repository" /> |
||||
|
<option name="url" value="https://repo1.maven.org/maven2" /> |
||||
|
</remote-repository> |
||||
|
<remote-repository> |
||||
|
<option name="id" value="jboss.community" /> |
||||
|
<option name="name" value="JBoss Community repository" /> |
||||
|
<option name="url" value="https://repository.jboss.org/nexus/content/repositories/public/" /> |
||||
|
</remote-repository> |
||||
|
</component> |
||||
|
</project> |
@ -0,0 +1,14 @@ |
|||||
|
<?xml version="1.0" encoding="UTF-8"?> |
||||
|
<project version="4"> |
||||
|
<component name="ExternalStorageConfigurationManager" enabled="true" /> |
||||
|
<component name="MavenProjectsManager"> |
||||
|
<option name="originalFiles"> |
||||
|
<list> |
||||
|
<option value="$PROJECT_DIR$/pom.xml" /> |
||||
|
</list> |
||||
|
</option> |
||||
|
</component> |
||||
|
<component name="ProjectRootManager" version="2" languageLevel="JDK_1_8" project-jdk-name="1.8" project-jdk-type="JavaSDK"> |
||||
|
<output url="file://$PROJECT_DIR$/out" /> |
||||
|
</component> |
||||
|
</project> |
@ -0,0 +1,124 @@ |
|||||
|
<?xml version="1.0" encoding="UTF-8"?> |
||||
|
<project version="4"> |
||||
|
<component name="Palette2"> |
||||
|
<group name="Swing"> |
||||
|
<item class="com.intellij.uiDesigner.HSpacer" tooltip-text="Horizontal Spacer" icon="/com/intellij/uiDesigner/icons/hspacer.png" removable="false" auto-create-binding="false" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="1" hsize-policy="6" anchor="0" fill="1" /> |
||||
|
</item> |
||||
|
<item class="com.intellij.uiDesigner.VSpacer" tooltip-text="Vertical Spacer" icon="/com/intellij/uiDesigner/icons/vspacer.png" removable="false" auto-create-binding="false" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="6" hsize-policy="1" anchor="0" fill="2" /> |
||||
|
</item> |
||||
|
<item class="javax.swing.JPanel" icon="/com/intellij/uiDesigner/icons/panel.png" removable="false" auto-create-binding="false" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3" /> |
||||
|
</item> |
||||
|
<item class="javax.swing.JScrollPane" icon="/com/intellij/uiDesigner/icons/scrollPane.png" removable="false" auto-create-binding="false" can-attach-label="true"> |
||||
|
<default-constraints vsize-policy="7" hsize-policy="7" anchor="0" fill="3" /> |
||||
|
</item> |
||||
|
<item class="javax.swing.JButton" icon="/com/intellij/uiDesigner/icons/button.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="3" anchor="0" fill="1" /> |
||||
|
<initial-values> |
||||
|
<property name="text" value="Button" /> |
||||
|
</initial-values> |
||||
|
</item> |
||||
|
<item class="javax.swing.JRadioButton" icon="/com/intellij/uiDesigner/icons/radioButton.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="3" anchor="8" fill="0" /> |
||||
|
<initial-values> |
||||
|
<property name="text" value="RadioButton" /> |
||||
|
</initial-values> |
||||
|
</item> |
||||
|
<item class="javax.swing.JCheckBox" icon="/com/intellij/uiDesigner/icons/checkBox.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="3" anchor="8" fill="0" /> |
||||
|
<initial-values> |
||||
|
<property name="text" value="CheckBox" /> |
||||
|
</initial-values> |
||||
|
</item> |
||||
|
<item class="javax.swing.JLabel" icon="/com/intellij/uiDesigner/icons/label.png" removable="false" auto-create-binding="false" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="0" anchor="8" fill="0" /> |
||||
|
<initial-values> |
||||
|
<property name="text" value="Label" /> |
||||
|
</initial-values> |
||||
|
</item> |
||||
|
<item class="javax.swing.JTextField" icon="/com/intellij/uiDesigner/icons/textField.png" removable="false" auto-create-binding="true" can-attach-label="true"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1"> |
||||
|
<preferred-size width="150" height="-1" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JPasswordField" icon="/com/intellij/uiDesigner/icons/passwordField.png" removable="false" auto-create-binding="true" can-attach-label="true"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1"> |
||||
|
<preferred-size width="150" height="-1" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JFormattedTextField" icon="/com/intellij/uiDesigner/icons/formattedTextField.png" removable="false" auto-create-binding="true" can-attach-label="true"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1"> |
||||
|
<preferred-size width="150" height="-1" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JTextArea" icon="/com/intellij/uiDesigner/icons/textArea.png" removable="false" auto-create-binding="true" can-attach-label="true"> |
||||
|
<default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3"> |
||||
|
<preferred-size width="150" height="50" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JTextPane" icon="/com/intellij/uiDesigner/icons/textPane.png" removable="false" auto-create-binding="true" can-attach-label="true"> |
||||
|
<default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3"> |
||||
|
<preferred-size width="150" height="50" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JEditorPane" icon="/com/intellij/uiDesigner/icons/editorPane.png" removable="false" auto-create-binding="true" can-attach-label="true"> |
||||
|
<default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3"> |
||||
|
<preferred-size width="150" height="50" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JComboBox" icon="/com/intellij/uiDesigner/icons/comboBox.png" removable="false" auto-create-binding="true" can-attach-label="true"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="2" anchor="8" fill="1" /> |
||||
|
</item> |
||||
|
<item class="javax.swing.JTable" icon="/com/intellij/uiDesigner/icons/table.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3"> |
||||
|
<preferred-size width="150" height="50" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JList" icon="/com/intellij/uiDesigner/icons/list.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="6" hsize-policy="2" anchor="0" fill="3"> |
||||
|
<preferred-size width="150" height="50" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JTree" icon="/com/intellij/uiDesigner/icons/tree.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3"> |
||||
|
<preferred-size width="150" height="50" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JTabbedPane" icon="/com/intellij/uiDesigner/icons/tabbedPane.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3"> |
||||
|
<preferred-size width="200" height="200" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JSplitPane" icon="/com/intellij/uiDesigner/icons/splitPane.png" removable="false" auto-create-binding="false" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3"> |
||||
|
<preferred-size width="200" height="200" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JSpinner" icon="/com/intellij/uiDesigner/icons/spinner.png" removable="false" auto-create-binding="true" can-attach-label="true"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1" /> |
||||
|
</item> |
||||
|
<item class="javax.swing.JSlider" icon="/com/intellij/uiDesigner/icons/slider.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1" /> |
||||
|
</item> |
||||
|
<item class="javax.swing.JSeparator" icon="/com/intellij/uiDesigner/icons/separator.png" removable="false" auto-create-binding="false" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3" /> |
||||
|
</item> |
||||
|
<item class="javax.swing.JProgressBar" icon="/com/intellij/uiDesigner/icons/progressbar.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="6" anchor="0" fill="1" /> |
||||
|
</item> |
||||
|
<item class="javax.swing.JToolBar" icon="/com/intellij/uiDesigner/icons/toolbar.png" removable="false" auto-create-binding="false" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="6" anchor="0" fill="1"> |
||||
|
<preferred-size width="-1" height="20" /> |
||||
|
</default-constraints> |
||||
|
</item> |
||||
|
<item class="javax.swing.JToolBar$Separator" icon="/com/intellij/uiDesigner/icons/toolbarSeparator.png" removable="false" auto-create-binding="false" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="0" hsize-policy="0" anchor="0" fill="1" /> |
||||
|
</item> |
||||
|
<item class="javax.swing.JScrollBar" icon="/com/intellij/uiDesigner/icons/scrollbar.png" removable="false" auto-create-binding="true" can-attach-label="false"> |
||||
|
<default-constraints vsize-policy="6" hsize-policy="0" anchor="0" fill="2" /> |
||||
|
</item> |
||||
|
</group> |
||||
|
</component> |
||||
|
</project> |
@ -0,0 +1,2 @@ |
|||||
|
<?xml version="1.0" encoding="UTF-8"?> |
||||
|
<module type="JAVA_MODULE" version="4" /> |
@ -0,0 +1,20 @@ |
|||||
|
<?xml version="1.0" encoding="UTF-8"?> |
||||
|
<project xmlns="http://maven.apache.org/POM/4.0.0" |
||||
|
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" |
||||
|
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> |
||||
|
<modelVersion>4.0.0</modelVersion> |
||||
|
|
||||
|
<groupId>com.woniu</groupId> |
||||
|
<artifactId>listdemo</artifactId> |
||||
|
<version>1.0-SNAPSHOT</version> |
||||
|
<dependencies> |
||||
|
<dependency> |
||||
|
<groupId>junit</groupId> |
||||
|
<artifactId>junit</artifactId> |
||||
|
<version>4.12</version> |
||||
|
<scope>compile</scope> |
||||
|
</dependency> |
||||
|
</dependencies> |
||||
|
|
||||
|
|
||||
|
</project> |
@ -0,0 +1,107 @@ |
|||||
|
package com.woniu; |
||||
|
|
||||
|
|
||||
|
import org.junit.Test; |
||||
|
|
||||
|
import java.util.HashMap; |
||||
|
import java.util.Iterator; |
||||
|
import java.util.Map; |
||||
|
import java.util.Set; |
||||
|
import java.util.concurrent.ConcurrentHashMap; |
||||
|
import java.util.concurrent.CopyOnWriteArraySet; |
||||
|
import java.util.stream.Collectors; |
||||
|
|
||||
|
/** |
||||
|
* 面试官:怎么删除 HashMap 中的元素?我一行代码搞定,赶紧拿去用! |
||||
|
*/ |
||||
|
public class TestHashMap { |
||||
|
public Map<String, String> initMap = new HashMap<String, String>() {{ |
||||
|
put("user1", "张三"); |
||||
|
put("user2", "李四"); |
||||
|
put("user3", "张三"); |
||||
|
put("user4", "李四"); |
||||
|
put("user5", "王五"); |
||||
|
put("user6", "赵六"); |
||||
|
put("user7", "李四"); |
||||
|
put("user8", "王五"); |
||||
|
}}; |
||||
|
|
||||
|
/** |
||||
|
* 使用 for 循环删除 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
@Test |
||||
|
public void remove1() { |
||||
|
Set<Map.Entry<String, String>> entries = new CopyOnWriteArraySet<>(initMap.entrySet()); |
||||
|
for (Map.Entry<String, String> entry : entries) { |
||||
|
if ("张三".equals(entry.getValue())) { |
||||
|
initMap.remove(entry.getKey()); |
||||
|
} |
||||
|
} |
||||
|
System.out.println(initMap); |
||||
|
} |
||||
|
|
||||
|
/** |
||||
|
* 使用 forEach 循环删除 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
@Test |
||||
|
public void remove2() { |
||||
|
ConcurrentHashMap<String, String> map = new ConcurrentHashMap<>(initMap); |
||||
|
map.forEach((k, v) -> { |
||||
|
if ("张三".equals(v)) { |
||||
|
map.remove(k); |
||||
|
} |
||||
|
}); |
||||
|
System.out.println(map); |
||||
|
} |
||||
|
|
||||
|
|
||||
|
/** |
||||
|
* 使用 Iterator 迭代器删除 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
@Test |
||||
|
public void remove3() { |
||||
|
Iterator<Map.Entry<String, String>> iterator = initMap.entrySet().iterator(); |
||||
|
while (iterator.hasNext()) { |
||||
|
Map.Entry<String, String> entry = iterator.next(); |
||||
|
if ("张三".equals(entry.getValue())) { |
||||
|
iterator.remove(); |
||||
|
} |
||||
|
} |
||||
|
System.out.println(initMap); |
||||
|
} |
||||
|
|
||||
|
|
||||
|
/** |
||||
|
* 使用 removeIf 删除 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
@Test |
||||
|
public void remove4() { |
||||
|
initMap.entrySet().removeIf(entry -> "张三".equals(entry.getValue())); |
||||
|
System.out.println(initMap); |
||||
|
} |
||||
|
|
||||
|
|
||||
|
|
||||
|
/** |
||||
|
* 使用 Stream 删除 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
@Test |
||||
|
public void remove5() { |
||||
|
Map<String, String> map = initMap.entrySet().stream() |
||||
|
.filter(entry -> !"张三".equals(entry.getValue())) |
||||
|
.collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)); |
||||
|
System.out.println(map); |
||||
|
} |
||||
|
|
||||
|
|
||||
|
|
||||
|
|
||||
|
|
||||
|
|
||||
|
|
||||
|
} |
@ -0,0 +1,112 @@ |
|||||
|
package com.woniu; |
||||
|
|
||||
|
|
||||
|
import org.junit.Test; |
||||
|
|
||||
|
import java.util.*; |
||||
|
import java.util.stream.Collectors; |
||||
|
|
||||
|
/** |
||||
|
* 面试官:怎么去除 List 中的重复元素?一行代码搞定,赶紧拿去用! |
||||
|
*/ |
||||
|
public class TestList { |
||||
|
|
||||
|
/** |
||||
|
* 3 个张三,2 个李强 |
||||
|
*/ |
||||
|
public List<String> initList = Arrays.asList( |
||||
|
"张三", |
||||
|
"李四", |
||||
|
"张三", |
||||
|
"周一", |
||||
|
"刘四", |
||||
|
"李强", |
||||
|
"李白", |
||||
|
"张三", |
||||
|
"李强", |
||||
|
"王五" |
||||
|
); |
||||
|
|
||||
|
/** |
||||
|
* for 循环添加去重 |
||||
|
* |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
public void remove1() { |
||||
|
List<String> list = new ArrayList(initList); |
||||
|
List<String> list2 = new ArrayList<>(); |
||||
|
for (String element : list) { |
||||
|
if (!list2.contains(element)) { |
||||
|
list2.add(element); |
||||
|
} |
||||
|
} |
||||
|
} |
||||
|
|
||||
|
|
||||
|
/** |
||||
|
* for 双循环去重 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
public void remove2() { |
||||
|
List<String> list = new ArrayList(initList); |
||||
|
for (int i = 0; i < list.size() - 1; i++) { |
||||
|
for (int j = list.size() - 1; j > i; j--) { |
||||
|
if (list.get(j).equals(list.get(i))) { |
||||
|
list.remove(j); |
||||
|
} |
||||
|
} |
||||
|
} |
||||
|
System.out.println(list); |
||||
|
} |
||||
|
|
||||
|
/** |
||||
|
* for 循环重复坐标去重 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
public void remove3() { |
||||
|
List<String> list = new ArrayList(initList); |
||||
|
List<String> list2 = new ArrayList(initList); |
||||
|
for (String element : list2) { |
||||
|
if (list.indexOf(element) != list.lastIndexOf(element)) { |
||||
|
list.remove(list.lastIndexOf(element)); |
||||
|
} |
||||
|
} |
||||
|
System.out.println(list); |
||||
|
} |
||||
|
|
||||
|
|
||||
|
/** |
||||
|
* Set 去重 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
public void remove4() { |
||||
|
List<String> list = new ArrayList(initList); |
||||
|
List<String> list2 = new ArrayList(new HashSet(list)); |
||||
|
System.out.println(list2); |
||||
|
} |
||||
|
|
||||
|
|
||||
|
/** |
||||
|
* Set 去重 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
@Test |
||||
|
public void remove5() { |
||||
|
List<String> list = new ArrayList(initList); |
||||
|
List<String> list2 = new ArrayList(new LinkedHashSet(list)); |
||||
|
System.out.println(list2); |
||||
|
} |
||||
|
|
||||
|
|
||||
|
|
||||
|
/** |
||||
|
* Stream 去重 |
||||
|
* @author: 蜗牛 |
||||
|
*/ |
||||
|
public void remove6() { |
||||
|
List<String> list = new ArrayList(initList); |
||||
|
list = list.stream().distinct().collect(Collectors.toList()); |
||||
|
System.out.println(list); |
||||
|
} |
||||
|
|
||||
|
} |
Binary file not shown.
Binary file not shown.
Binary file not shown.
Loading…
Reference in new issue