Freemarker 模板无法解析 Java 对象

Question

我有一个 POJO（class 为每个字段设置了 getter），我将其发送回另一个 class 中的变量，其中已完成模板配置。当 ftl 尝试填充视图时，我以某种方式收到错误消息。

我不知道如何将这种类型的对象呈现给模板：org.test.config.TransformerInfoBuilder。这是错误来自的代码：

[line 13, column 5 in templates/ConfigMain.ftl]
list TransformerInfoBuilders as TransformerInfoBuilder

Java 错误堆栈跟踪：

freemarker.template.TemplateModelException: Don't know how to present an object of this type to a template: org.test.config.TransformerInfoBuilder
    at freemarker.template.SimpleObjectWrapper.handleUnknownType(SimpleObjectWrapper.java:139)
    at freemarker.template.SimpleObjectWrapper.wrap(SimpleObjectWrapper.java:116)
    at freemarker.template.WrappingTemplateModel.wrap(WrappingTemplateModel.java:131)
    at freemarker.template.SimpleSequence.get(SimpleSequence.java:197)
    at freemarker.template.IteratorBlock$Context.runLoop(IteratorBlock.java:163)
    at freemarker.template.Environment.visit(Environment.java:316)
    at freemarker.template.IteratorBlock.accept(IteratorBlock.java:94)
    at freemarker.template.Environment.visit(Environment.java:180)
    at freemarker.template.IfBlock.accept(IfBlock.java:81)
    at freemarker.template.Environment.visit(Environment.java:180)
    at freemarker.template.MixedContent.accept(MixedContent.java:91)
    at freemarker.template.Environment.visit(Environment.java:180)
    at freemarker.template.Environment.process(Environment.java:166)
    at freemarker.template.Template.process(Template.java:238)
    at org.mule.config.ConfigLoader.main(ConfigLoader.java:116)

ftl如下。

<#if TransformerInfoBuilders?has_content> 
<#list TransformerInfoBuilders as TransformerInfoBuilder>
<flow name="${TransformerInfoBuilder.id}">
</flow>
</#list>
<#else>
no content
</#if>

Java class 用于创建对象。

public class TransformerInfoBuilder {

  String id="";
  String name="";
  String returnClass="";
  String ignoreBadInput="";
  String encoding="";
  String mimeType="";
  String templateName="";

 public TransformerInfoBuilder(String id, String name,String returnClass, String encoding, String ignoreBadInput)
 { 
     this.id=id;
     this.name=name;
     this.returnClass=returnClass;
     this.encoding=encoding;
     this.ignoreBadInput=ignoreBadInput;

 }
 public void setid(String id)
 {
     this.id=id;
 }

 public void setname(String name)
 {
     this.name=name;
 }

 public String getname()
 {
     return this.name;
 }

 public String getid()
 {
     return this.id;
 }

 public String getreturnClass()
 {
     return this.returnClass;

 }

 public String getignoreBadInput()
 {
     return this.ignoreBadInput;
 }

 public String getencoding()
 {
     return this.encoding;
 }
}

Java class 调用配置器的地方：

public class ConfigLoader {

public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException, SQLException, IOException {

        Configuration cfg = new Configuration();
        Template template = cfg.getTemplate("/templates/ConfigMain.ftl");
        Connection dbconn=null;
        Statement stmt=null;
        ResultSet rs= null;
        String id="";
        HashMap<String,Map<String,String>> tinfo= new HashMap<String,Map<String,String>> ();
        List<String> flowList = new ArrayList<String>();
        List<TransformerInfoBuilder> TransformerInfoBuilders = new ArrayList<TransformerInfoBuilder>();
        //Map<String,Object> flistfinal = new HashMap<String,Object>();
        Map<String, Object> data = new HashMap<String, Object>();
        List<Map<String,ArrayList<String>>> mapsfinal = new ArrayList<Map<String,ArrayList<String>>>();


        try {
            // Load the template

            String configId =args[0]; 

            System.out.println("+++++++++++++++++++++++configID is " + configId + " +++++++++++++++++++++++");

            dbconn=DBConnection.connection();
            System.out.println("\n\n++++++++++++++++++ Obtained DB connection ++++++++++++++++");
            stmt = dbconn.createStatement();
            System.out.println("\n\n++++++++++++++++++ Querying for Config Application Name ++++++++");
            rs = stmt.executeQuery("SELECT * FROM FlowInfo where ConfigFileId =" + configId);

            while (rs.next()) {
                id = rs.getString("FlowID");
                flowList.add(id);

            }






            TransformerInfoBuilders=Transformer.TransformerInfo(flowList);

             data.put("TransformerInfoBuilders",TransformerInfoBuilders);





               data.put("message","#[payload]");
                Writer writer = new FileWriter("output/MainConfig.xml");
                template.process(data, writer);
                writer.flush();
                writer.close();
                //out.flush();
            } catch (IOException e) {
                e.printStackTrace();
            } catch (TemplateException et) {
                et.printStackTrace();
            }finally {
                try { if (rs != null) rs.close(); } catch (SQLException e) { e.printStackTrace(); }
                try { if (stmt != null) stmt.close(); } catch (SQLException e) { e.printStackTrace(); }
                try { if (dbconn != null) dbconn.close(); } catch (SQLException e) { e.printStackTrace(); }
                }

}
}

关于我在这里可能做错了什么的任何指示？？

谢谢萨利姆

Answer 1

在扩展 DefaultObjectWrapper class 之后问题就解决了。我不得不将它升级到 Freemarker.jar 的更高版本。

Freemarker 模板无法解析 Java 对象

Freemarker template not able to parse the Java object

java

templates

freemarker