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  • 使用PULL解析XML文件

    XmlPull和Sax类似，是基于流（stream）操作文件，然后根据节点事件回调开发者编写的处理程序。因为是基于流的处理，因此Xmlpull和 Sax都比较节约内存资源，不会象Dom那样要把所有节点以对橡树的形式展现在内存中。 但Xmlpull比Sax更简明，而且不需要扫描完整个流。

    下面来看一个pull解析xml的例子：

    student.xml:

    [html] view plaincopyprint?
    1. <?xmlversion="1.0"encoding="utf-8"?>
    2. <root>
    3. <studentid="1"group="1">
    4. <name>张三</name>
    5. <sex>男</sex>
    6. <age>18</age>
    7. <email>zhangsan@163.com</email>
    8. <birthday>1987-06-08</birthday>
    9. <memo>好学生</memo>
    10. </student>
    11. <studentid="2"group="2">
    12. <name>李四</name>
    13. <sex>女</sex>
    14. <age>18</age>
    15. <email>lisi@163.com</email>
    16. <birthday>1987-06-08</birthday>
    17. <memo>好学生</memo>
    18. </student>
    19. <studentid="3"group="3">
    20. <name>小王</name>
    21. <sex>男</sex>
    22. <age>18</age>
    23. <email>xiaowang@163.com</email>
    24. <birthday>1987-06-08</birthday>
    25. <memo>好学生</memo>
    26. </student>
    27. <studentid="4"group="4">
    28. <name>小张</name>
    29. <sex>男</sex>
    30. <age>18</age>
    31. <email>xiaozhang@163.com</email>
    32. <birthday>1987-06-08</birthday>
    33. <memo>好学生</memo>
    34. </student>
    35. <studentid="5"group="5">
    36. <name>小明</name>
    37. <sex>男</sex>
    38. <age>18</age>
    39. <email>xiaoming@163.com</email>
    40. <birthday>1987-06-08</birthday>
    41. <memo>好学生</memo>
    42. </student>
    43. </root>
    <?xml version="1.0" encoding="utf-8"?>  
    <root>  
        <student id="1" group="1">  
            <name>张三</name>  
            <sex>男</sex>  
            <age>18</age>  
            <email>zhangsan@163.com</email>  
            <birthday>1987-06-08</birthday>  
            <memo>好学生</memo>  
        </student>  
        <student id="2" group="2">  
            <name>李四</name>  
            <sex>女</sex>  
            <age>18</age>  
            <email>lisi@163.com</email>  
            <birthday>1987-06-08</birthday>  
            <memo>好学生</memo>  
        </student>  
        <student id="3" group="3">  
            <name>小王</name>  
            <sex>男</sex>  
            <age>18</age>  
            <email>xiaowang@163.com</email>  
            <birthday>1987-06-08</birthday>  
            <memo>好学生</memo>  
        </student>  
        <student id="4" group="4">  
            <name>小张</name>  
            <sex>男</sex>  
            <age>18</age>  
            <email>xiaozhang@163.com</email>  
            <birthday>1987-06-08</birthday>  
            <memo>好学生</memo>  
        </student>  
        <student id="5" group="5">  
            <name>小明</name>  
            <sex>男</sex>  
            <age>18</age>  
            <email>xiaoming@163.com</email>  
            <birthday>1987-06-08</birthday>  
            <memo>好学生</memo>  
        </student>  
    </root>

    对应的bean：

    [html] view plaincopyprint?
    1. public class Student {
    3. private int id;
    4. private int group;
    5. private String name;
    6. private String sex;
    7. private int age;
    8. private String email;
    9. private String memo;
    10. private String birthday;
    11. public int getId() {
    12. return id;
    13. }
    14. public void setId(int id) {
    15. this.id = id;
    16. }
    17. public int getGroup() {
    18. return group;
    19. }
    20. public void setGroup(int group) {
    21. this.group = group;
    22. }
    23. public String getName() {
    24. return name;
    25. }
    26. public void setName(String name) {
    27. this.name = name;
    28. }
    29. public String getSex() {
    30. return sex;
    31. }
    32. public void setSex(String sex) {
    33. this.sex = sex;
    34. }
    35. public int getAge() {
    36. return age;
    37. }
    38. public void setAge(int age) {
    39. this.age = age;
    40. }
    41. public String getEmail() {
    42. return email;
    43. }
    44. public void setEmail(String email) {
    45. this.email = email;
    46. }
    47. public String getMemo() {
    48. return memo;
    49. }
    50. public void setMemo(String memo) {
    51. this.memo = memo;
    52. }
    53. public String getBirthday() {
    54. return birthday;
    55. }
    56. public void setBirthday(String birthday) {
    57. this.birthday = birthday;
    58. }
    60. } 
    public class Student {  
    
    private int id;  
    private int group;  
    private String name;  
    private String sex;  
    private int age;  
    private String email;  
    private String memo;  
    private String birthday;  
    public int getId() {  
        return id;  
    }  
    public void setId(int id) {  
        this.id = id;  
    }  
    public int getGroup() {  
        return group;  
    }  
    public void setGroup(int group) {  
        this.group = group;  
    }  
    public String getName() {  
        return name;  
    }  
    public void setName(String name) {  
        this.name = name;  
    }  
    public String getSex() {  
        return sex;  
    }  
    public void setSex(String sex) {  
        this.sex = sex;  
    }  
    public int getAge() {  
        return age;  
    }  
    public void setAge(int age) {  
        this.age = age;  
    }  
    public String getEmail() {  
        return email;  
    }  
    public void setEmail(String email) {  
        this.email = email;  
    }  
    public String getMemo() {  
        return memo;  
    }  
    public void setMemo(String memo) {  
        this.memo = memo;  
    }  
    public String getBirthday() {  
        return birthday;  
    }  
    public void setBirthday(String birthday) {  
        this.birthday = birthday;  
    }  
      
}


    主要的解析和现实类：

    [html] view plaincopyprint?
    1. import java.io.InputStream;
    2. import java.util.ArrayList;
    3. import java.util.List;
    5. import org.xmlpull.v1.XmlPullParser;
    6. import org.xmlpull.v1.XmlPullParserFactory;
    8. import android.app.Activity;
    9. import android.os.Bundle;
    10. import android.os.Handler;
    11. import android.os.Message;
    12. import android.view.ViewGroup.LayoutParams;
    13. import android.widget.LinearLayout;
    15. import android.widget.TextView;
    17. public class PullActivity extends Activity implements Runnable{
    19. private TextView pullTextView ;
    20. private LinearLayout layout;
    21. private Handler handler=new Handler(){
    22. public void handleMessage(android.os.Message msg) {
    23. List<Student>lists=(List<Student>) msg.obj;
    24. for(int i=0;i<lists.size();i++){
    25. Student student=lists.get(i);
    26. StringBuffer sb=new StringBuffer();
    27. sb.append(student.getId()+" ").append(student.getName()+" ")
    28. .append(student.getAge()+" ").append(student.getSex()+" ").append(student.getBirthday()+" ")
    29. .append(student.getEmail()+" ").append(student.getGroup()+" ");
    30. TextView txt=new TextView(getApplicationContext());
    31. txt.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
    32. txt.setText(sb.toString());
    33. layout.addView(txt);
    34. }
    35. };
    36. };
    37. @Override
    38. protected void onCreate(Bundle savedInstanceState) {
    39. // TODO Auto-generated method stub
    40. super.onCreate(savedInstanceState);
    41. setContentView(R.layout.pull);
    43. pullTextView=(TextView) this.findViewById(R.id.pullTextView);
    44. layout=(LinearLayout) this.findViewById(R.id.layout);
    45. new Thread(this).start();
    49. }
    50. //pull解析xml
    51. public List<Student> pullParseXml(){
    52. List<Student>lists=null;
    53. Student student=null;
    55. try {
    56. XmlPullParserFactory factory=XmlPullParserFactory.newInstance();
    57. //获取XmlPullParser实例
    58. XmlPullParser pullParser=factory.newPullParser();
    59. InputStream in=this.getClass().getClassLoader().getResourceAsStream("student.xml");
    60. pullParser.setInput(in, "UTF-8");
    61. //开始
    62. int eventType=pullParser.getEventType();
    64. while(eventType!=XmlPullParser.END_DOCUMENT){
    65. String nodeName=pullParser.getName();
    66. switch (eventType) {
    67. //文档开始
    68. case XmlPullParser.START_DOCUMENT:
    69. lists=new ArrayList<Student>();
    70. break;
    72. //开始节点
    73. case XmlPullParser.START_TAG:
    74. if("student".equals(nodeName)){
    75. student=new Student();
    76. student.setId(Integer.parseInt(pullParser.getAttributeValue(0)));
    77. student.setGroup(Integer.parseInt(pullParser.getAttributeValue(1)));
    78. }else if("name".equals(nodeName)){
    79. student.setName(pullParser.nextText());
    80. }else if("sex".equals(nodeName)){
    81. student.setSex(pullParser.nextText());
    82. }else if("age".equals(nodeName)){
    83. student.setAge(Integer.parseInt(pullParser.nextText()));
    84. }else if("email".equals(nodeName)){
    85. student.setEmail(pullParser.nextText());
    86. }else if("birthday".equals(nodeName)){
    87. student.setBirthday(pullParser.nextText());
    88. }else if("memo".equals(nodeName)){
    89. student.setMemo(pullParser.nextText());
    90. }
    91. break;
    92. //结束节点
    93. case XmlPullParser.END_TAG:
    94. if("student".equals(nodeName)){
    95. lists.add(student);
    96. student=null;
    97. }
    98. break;
    99. default:
    100. break;
    101. }
    102. // 手动的触发下一个事件
    103. eventType=pullParser.next();
    104. }
    105. } catch (Exception e) {
    106. // TODO Auto-generated catch block
    107. e.printStackTrace();
    108. }
    109. return lists;
    111. }
    112. @Override
    113. public void run() {
    114. // TODO Auto-generated method stub
    115. List<Student>lists=pullParseXml();
    116. Message msg=handler.obtainMessage();
    117. msg.obj=lists;
    118. handler.sendMessage(msg);
    119. }
    120. } 
    import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserFactory;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.ViewGroup.LayoutParams;
import android.widget.LinearLayout;

import android.widget.TextView;

public class PullActivity extends Activity implements Runnable{

	private TextView pullTextView ;
	private LinearLayout layout;
	private Handler handler=new Handler(){
		 public void handleMessage(android.os.Message msg) {
			 List<Student> lists=(List<Student>) msg.obj;
			 for(int i=0;i<lists.size();i++){
				 Student student=lists.get(i);
				 StringBuffer sb=new StringBuffer();
				 sb.append(student.getId()+"  ").append(student.getName()+"  ")
				 .append(student.getAge()+"  ").append(student.getSex()+" ").append(student.getBirthday()+"  ")
				 .append(student.getEmail()+"  ").append(student.getGroup()+"  ");
				 TextView txt=new TextView(getApplicationContext());
				 txt.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
				 txt.setText(sb.toString());
				 layout.addView(txt);
			 }
		 };
	};
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);
		setContentView(R.layout.pull);
		
		pullTextView=(TextView) this.findViewById(R.id.pullTextView);
		layout=(LinearLayout) this.findViewById(R.id.layout);
		new Thread(this).start();
		
		 
		 
	}
	//pull解析xml
	public List<Student> pullParseXml(){
		List<Student> lists=null;
		Student student=null;
		
		try {
			XmlPullParserFactory factory=XmlPullParserFactory.newInstance();
			//获取XmlPullParser实例
			XmlPullParser pullParser=factory.newPullParser();
			InputStream in=this.getClass().getClassLoader().getResourceAsStream("student.xml");
			pullParser.setInput(in, "UTF-8");
			//开始
			int eventType=pullParser.getEventType();
			
			while(eventType!=XmlPullParser.END_DOCUMENT){
				String nodeName=pullParser.getName();
				switch (eventType) {
				//文档开始
				case XmlPullParser.START_DOCUMENT:
					 lists=new ArrayList<Student>();
					break;

					//开始节点
				case XmlPullParser.START_TAG:
					if("student".equals(nodeName)){
						student=new Student();
						student.setId(Integer.parseInt(pullParser.getAttributeValue(0)));
						student.setGroup(Integer.parseInt(pullParser.getAttributeValue(1)));
					}else if("name".equals(nodeName)){
						student.setName(pullParser.nextText());
					}else if("sex".equals(nodeName)){
						student.setSex(pullParser.nextText());
					}else if("age".equals(nodeName)){
						student.setAge(Integer.parseInt(pullParser.nextText()));
					}else if("email".equals(nodeName)){
						student.setEmail(pullParser.nextText());
					}else if("birthday".equals(nodeName)){
						student.setBirthday(pullParser.nextText());
					}else if("memo".equals(nodeName)){
						student.setMemo(pullParser.nextText());
					}
					break;
					//结束节点
				case XmlPullParser.END_TAG:
					if("student".equals(nodeName)){
						lists.add(student);
						student=null;
					}
					break;
				default:
					break;
				}
				 // 手动的触发下一个事件  
				eventType=pullParser.next();
			}
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return lists;
		
	}
	@Override
	public void run() {
		// TODO Auto-generated method stub
		List<Student> lists=pullParseXml();
		Message msg=handler.obtainMessage();
		msg.obj=lists;
		handler.sendMessage(msg);
	}
}

    注意xml中的<?xml version="1.0" encoding="utf-8"?> 这句话要顶格显示，不要留空隙，附则错了很难调试的。

    解析后效果：
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  • 原文地址：https://www.cnblogs.com/leischen/p/2958057.html
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