PULL解析XML

Android中常见的xml解析方式有sax、dom和pull，下面我们就看一个小巧轻便，解析方便，速度很快的pull方式的实例。

先建一个xml吧：mission.xml

[html]
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<?xml version="1.0" encoding="UTF-8" ?>
<region id="region_1" width="100" height="800">
<element id="1" type="20">Chinese</element>
<element id="2" type="20">English</element>
</region>

建region的实体: Region.java

[java]
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package com.hebaijun.xmlparser;

import java.util.List;

public class Region {
private String id;
private int width;
private int height;
private List<Element> elements;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public int getWidth() {
return width;
}
public void setWidth(int width) {
this.width = width;
}
public int getHeight() {
return height;
}
public void setHeight(int height) {
this.height = height;
}
public List<Element> getElements() {
return elements;
}
public void setElements(List<Element> elements) {
this.elements = elements;
}

}

Element的实体：Element.java

[java]
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package com.hebaijun.xmlparser;

public class Element {
private String id;
private String type;
private String value;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
}

最后是实例代码：

[java]
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package com.hebaijun.xmlparser;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

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

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;

public class XmlParserActivity extends Activity {
/** Called when the activity is first created. */
Region region;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//取xml的路径
String xmlPath = getExternalStoragePath() + "/mission.xml";
try {
region = parser(xmlPath);
} catch (XmlPullParserException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
//打印一些结果
Log.v("region_id", region.getId());
for (Element element : region.getElements()) {
Log.v("element_value", element.getValue());
}
}

//获取sdcard路径
public static String getExternalStoragePath(){
//获取状态
String state = android.os.Environment.getExternalStorageState();
//判断是否可读
if (android.os.Environment.MEDIA_MOUNTED.equals(state)) {
if (android.os.Environment.getExternalStorageDirectory().canRead()) {
return android.os.Environment.getExternalStorageDirectory().getPath();
}
}
return null;
}

public Region parser(String path) throws XmlPullParserException, IOException{
File xmlFile = new File(path);
Element xmlElement = null;
List<Element> xmlElements = null;
Region xmlRegion = null;
if (xmlFile.exists()) {
InputStream slideInputStream = new FileInputStream(path);
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(true);
XmlPullParser xpp = factory.newPullParser();
xpp.setInput(slideInputStream, "UTF-8");
int eventType = xpp.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
if(eventType == XmlPullParser.START_DOCUMENT) {

} else if(eventType == XmlPullParser.START_TAG) {
String startName = xpp.getName();
if (startName.equalsIgnoreCase("region")) {
xmlRegion = new Region();
xmlElements = new ArrayList<Element>();
int count = xpp.getAttributeCount();
for (int i = 0; i < count; i++) {
String name = xpp.getAttributeName(i);
String value = xpp.getAttributeValue(i);
if (name.equalsIgnoreCase("id")) {
xmlRegion.setId(value);
} else if (name.equalsIgnoreCase("width")) {
xmlRegion.setWidth(Integer.parseInt(value));
} else if (name.equalsIgnoreCase("height")) {
xmlRegion.setHeight(Integer.parseInt(value));
}
}
} else if (startName.equalsIgnoreCase("element")) {
xmlElement = new Element();
int count = xpp.getAttributeCount();
for (int i = 0; i < count; i++) {
String name = xpp.getAttributeName(i);
String value = xpp.getAttributeValue(i);
if (name.equalsIgnoreCase("id")) {
xmlElement.setId(value);
} else if (name.equalsIgnoreCase("type")) {
xmlElement.setType(value);
}
}
//元素的text值
xpp.next();
xmlElement.setValue(xpp.getText());
}
} else if(eventType == XmlPullParser.END_TAG) {
String endName = xpp.getName();
if (endName.equalsIgnoreCase("region")) {
if (xmlElements != null) {
xmlRegion.setElements(xmlElements);
}
} else if (endName.equalsIgnoreCase("element")) {
xmlElements.add(xmlElement);
}
}
//下一个元素
eventType = xpp.next();
}

//关闭输入流
if (slideInputStream != null) {
slideInputStream.close();
slideInputStream = null;
}
}
return xmlRegion;
}
}

PS: XML中 notice貌似是关键字，如果有的话，会导致失败 提示attr value delimiter missing!