Bootstrap嵌入jqGrid，使你的table牛逼起来(3)

####④ 、jqGrid的数据操作

数据操作部分，我认为包含有 检索参数传递、分页排序参数传递、sql语句的编写。

关于参数传递，前端的参数封装在③中已有介绍，我们来看一看controller中如何处理数据的。

首先，我们来定义PageGrid，也就是jqGrid中xmlReader的数据源。

package com.honzh.common.page;

import java.util.List;

import com.thoughtworks.xstream.annotations.XStreamAlias;

@XStreamAlias("pageGrid")
@SuppressWarnings("rawtypes")
public class PageGrid {
    private int page;
    private int total;
    private int records;

    private List data;

    public int getPage() {
        return this.page;
    }

    public void setPage(int page) {
        this.page = page;
    }

    public int getTotal() {
        return this.total;
    }

    public void setTotal(int total) {
        this.total = total;
    }

    public int getRecords() {
        return this.records;
    }

    public void setRecords(int records) {
        this.records = records;
    }

    public List getData() {
        return this.data;
    }

    public void setData(List data) {
        this.data = data;
    }
}


      

XStreamComponent.java

package com.honzh.common.page;

import org.apache.commons.lang.StringUtils;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.converters.Converter;
import com.thoughtworks.xstream.io.xml.DomDriver;
import com.thoughtworks.xstream.mapper.DefaultMapper;
import com.thoughtworks.xstream.mapper.XStream11XmlFriendlyMapper;

public class XStreamComponent {
    private XStream xstream;

    public static XStreamComponent newInstance() {
        XStreamComponent xmlComponent = new XStreamComponent();
        xmlComponent.alias(new Class[] { PageGrid.class });
        
        return xmlComponent;
    }

    public XStreamComponent() {
        this.xstream = new XStream(new DomDriver());
    }

    public String toXML(Object obj) {
        return this.xstream.toXML(obj);
    }

    public String toPageXML(Object obj) {
        registerConverter(new MapCustomConverter(new DefaultMapper(XStream11XmlFriendlyMapper.class.getClassLoader())));
        return toXML(obj);
    }

    public Object fromPageXML(String xml) {
        registerConverter(new MapCustomConverter(new DefaultMapper(XStream11XmlFriendlyMapper.class.getClassLoader())));
        return fromXML(xml);
    }

    public Object fromXML(String xml) {
        return this.xstream.fromXML(xml);
    }

    @SuppressWarnings("rawtypes")
    public void processAnnotations(Class type) {
        this.xstream.processAnnotations(type);
    }

    @SuppressWarnings("rawtypes")
    public void processAnnotations(Class[] types) {
        this.xstream.processAnnotations(types);
    }

    @SuppressWarnings("rawtypes")
    public void alias(String name, Class type) {
        this.xstream.alias(name, type);
    }

    @SuppressWarnings("rawtypes")
    public void alias(Class[] types) {
        for (Class type : types) {
            String className = type.getName();
            try {
                String[] classNames = StringUtils.split(className, ".");
                this.xstream.alias(classNames[(classNames.length - 1)], type);
            } catch (Exception ex) {
                this.xstream.alias(className, type);
            }
        }
    }

    public void registerConverter(Converter converter) {
        this.xstream.registerConverter(converter);
    }

    @SuppressWarnings("rawtypes")
    public void useAttributeFor(Class definedIn, String fieldName) {
        this.xstream.useAttributeFor(definedIn, fieldName);
    }
}


      

MapCustomConverter.java

package com.honzh.common.page;

import java.util.HashMap;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Map;

import com.thoughtworks.xstream.converters.MarshallingContext;
import com.thoughtworks.xstream.converters.UnmarshallingContext;
import com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.mapper.Mapper;

public class MapCustomConverter extends AbstractCollectionConverter {
    public MapCustomConverter(Mapper mapper) {
        super(mapper);
    }

    @SuppressWarnings("rawtypes")
    public boolean canConvert(Class type) {
        return (type.equals(HashMap.class)) || (type.equals(Hashtable.class))
                || (type.getName().equals("java.util.LinkedHashMap"))
                || (type.getName().equals("sun.font.AttributeMap"));
    }

    @SuppressWarnings({ "rawtypes" })
    public void marshal(Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
        Map map = (Map) source;
        for (Iterator iterator = map.entrySet().iterator(); iterator.hasNext();) {
            Map.Entry entry = (Map.Entry) iterator.next();
            writer.startNode(entry.getKey() == null ? "null" : entry.getKey().toString());
            writer.setValue(entry.getValue() == null ? "" : entry.getValue().toString());
            writer.endNode();
        }
    }

    @SuppressWarnings("rawtypes")
    public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
        Map map = (Map) createCollection(context.getRequiredType());
        populateMap(reader, context, map);
        return map;
    }

    @SuppressWarnings({ "rawtypes", "unchecked" })
    protected void populateMap(HierarchicalStreamReader reader, UnmarshallingContext context, Map map) {
        while (reader.hasMoreChildren()) {
            reader.moveDown();
            Object key = reader.getNodeName();
            Object value = reader.getValue();
            map.put(key, value);
            reader.moveUp();
        }
    }
}