@210 Implemented parsing of expressions.

Pending: expression with one boolean value, finish IfNode, implement ListNode

Author: ericbn

javalite-templator/src/main/java/org/javalite/templator/AndExp.java

@@ -0,0 +1,25 @@
+package org.javalite.templator;
+
+import java.util.Map;
+
+/**
+ * @author Eric Nielsen
+ */
+class AndExp extends Exp {
+    private final Exp leftExp;
+    private final Exp rightExp;
+
+    AndExp(Exp leftExp, Exp rightExp) {
+        this.leftExp = leftExp;
+        this.rightExp = rightExp;
+    }
+
+    @Override
+    boolean resultWith(Map values) {
+        if (leftExp.resultWith(values)) {
+            return rightExp.resultWith(values);
+        } else {
+            return false;
+        }
+    }
+}

javalite-templator/src/main/java/org/javalite/templator/Comparison.java

@@ -0,0 +1,23 @@
+package org.javalite.templator;
+
+import java.util.Map;
+
+/**
+ * @author Eric Nielsen
+ */
+class Comparison extends Exp {
+    private final Identifiers leftIdent;
+    private final Op op;
+    private final Identifiers rightIdent;
+
+    Comparison(Identifiers leftIdent, Op op, Identifiers rightIdent) {
+        this.leftIdent = leftIdent;
+        this.op = op;
+        this.rightIdent = rightIdent;
+    }
+
+    @Override
+    boolean resultWith(Map values) {
+        return op.resultWith(leftIdent.valueFrom(values), rightIdent.valueFrom(values));
+    }
+}

javalite-templator/src/main/java/org/javalite/templator/ConstNode.java

@@ -1,5 +1,6 @@
 package org.javalite.templator;
 
+import java.io.IOException;
 import java.util.Map;
 
 /**
@@ -8,20 +9,20 @@
  * @author Igor Polevoy
  * @author Eric Nielsen
  */
-class ConstNode extends TemplateNode {
+class ConstNode extends Node {
     private final String value;
 
-    public ConstNode(String value) {
+    ConstNode(String value) {
         this.value = value;
     }
 
     @Override
-    public void process(Map values, Appendable appendable) throws Exception {
+    void process(Map values, Appendable appendable) throws IOException {
         appendable.append(value);
     }
 
     @Override
-    public String toString(){
+    public String toString() {
         return value;
     }
 }

javalite-templator/src/main/java/org/javalite/templator/Exp.java

@@ -0,0 +1,10 @@
+package org.javalite.templator;
+
+import java.util.Map;
+
+/**
+ * @author Eric Nielsen
+ */
+abstract class Exp {
+    abstract boolean resultWith(Map values);
+}

javalite-templator/src/main/java/org/javalite/templator/Identifiers.java

@@ -0,0 +1,56 @@
+package org.javalite.templator;
+
+import java.util.List;
+import java.util.Map;
+import org.javalite.templator.TemplateException;
+import static org.javalite.common.Inflector.capitalize;
+
+/**
+ * @author Eric Nielsen
+ */
+class Identifiers {
+    private final String firstIdentifier;
+    private final List<String> identifiers;
+
+    Identifiers(String firstIdentifier, List<String> identifiers) {
+        this.firstIdentifier = firstIdentifier;
+        this.identifiers = identifiers;
+    }
+
+    private Object valueOf(Object obj, String propertyName) {
+        try {
+            if (propertyName.endsWith("()")) {
+                return obj.getClass().getMethod(propertyName.substring(0, propertyName.length() - 2)).invoke(obj);
+            }
+        } catch (Exception e) {
+            throw new TemplateException(e);
+        }
+        if (obj instanceof Map) {
+            return ((Map) obj).get(propertyName);
+        }
+        try {
+            // try generic get method
+            return obj.getClass().getMethod("get", String.class).invoke(obj, propertyName);
+        } catch (Exception e) {
+            try {
+                // try javabean property
+                return obj.getClass().getMethod("get" + capitalize(propertyName)).invoke(obj);
+            } catch (Exception e1) {
+                // try public field
+                try {
+                    return obj.getClass().getDeclaredField(propertyName).get(obj);
+                } catch (Exception e2) {
+                }
+            }
+        }
+        return null;
+    }
+
+    Object valueFrom(Map values) {
+        Object obj = values.get(firstIdentifier);
+        for (String identifier : identifiers) {
+            obj = valueOf(obj, identifier);
+        }
+        return obj;
+    }
+}

javalite-templator/src/main/java/org/javalite/templator/IfNode.java

@@ -0,0 +1,22 @@
+package org.javalite.templator;
+
+import java.io.IOException;
+import java.util.Map;
+
+/**
+ * This terminal node represents a variable chunk of text in template.
+ *
+ * @author Eric Nielsen
+ */
+class IfNode extends ParentNode {
+    private final Exp exp;
+
+    IfNode(Exp exp) {
+        this.exp = exp;
+    }
+
+    @Override
+    void process(Map values, Appendable appendable) throws IOException {
+        appendable.append(String.valueOf(exp.resultWith(values)));
+    }
+}

javalite-templator/src/main/java/org/javalite/templator/TemplateNode.java renamed to javalite-templator/src/main/java/org/javalite/templator/Node.java

@@ -1,11 +1,12 @@
 package org.javalite.templator;
 
+import java.io.IOException;
 import java.util.Map;
 
 /**
  * @author Igor Polevoy
  * @author Eric Nielsen
  */
-abstract class TemplateNode {
-    abstract void process(Map values, Appendable appendable) throws Exception;
+abstract class Node {
+    abstract void process(Map values, Appendable appendable) throws IOException;
 }

javalite-templator/src/main/java/org/javalite/templator/NotExp.java

@@ -0,0 +1,19 @@
+package org.javalite.templator;
+
+import java.util.Map;
+
+/**
+ * @author Eric Nielsen
+ */
+class NotExp extends Exp {
+    private final Exp exp;
+
+    NotExp(Exp exp) {
+        this.exp = exp;
+    }
+    
+    @Override
+    boolean resultWith(Map values) {
+        return !exp.resultWith(values);
+    }
+}

javalite-templator/src/main/java/org/javalite/templator/Op.java

@@ -0,0 +1,45 @@
+package org.javalite.templator;
+
+/**
+ * @author Eric Nielsen
+ */
+enum Op {
+    eq {
+        @Override boolean resultWith(Object obj1, Object obj2) {
+            return obj1 == null ? obj2 == null : (obj2 == null ? false : obj1.equals(obj2));
+        }
+    },
+    gt {
+        @Override boolean resultWith(Object obj1, Object obj2) {
+            return compare(obj1, obj2) > 0;
+        }
+    },
+    gte {
+        @Override boolean resultWith(Object obj1, Object obj2) {
+            return compare(obj1, obj2) >= 0;
+        }
+    },
+    lt {
+        @Override boolean resultWith(Object obj1, Object obj2) {
+            return compare(obj1, obj2) < 0;
+        }
+    },
+    lte {
+        @Override boolean resultWith(Object obj1, Object obj2) {
+            return compare(obj1, obj2) <= 0;
+        }
+    },
+    neq {
+        @Override boolean resultWith(Object obj1, Object obj2) {
+            return obj1 == null ? obj2 != null : (obj2 == null ? true : !obj1.equals(obj2));
+        }
+    };
+
+    boolean resultWith(Object obj1, Object obj2) {
+        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
+    }
+
+    int compare(Object obj1, Object obj2) {
+        return ((Comparable) obj1).compareTo(obj2);
+    }
+}

javalite-templator/src/main/java/org/javalite/templator/OrExp.java

@@ -0,0 +1,25 @@
+package org.javalite.templator;
+
+import java.util.Map;
+
+/**
+ * @author Eric Nielsen
+ */
+class OrExp extends Exp {
+    private final Exp leftExp;
+    private final Exp rightExp;
+
+    OrExp(Exp leftExp, Exp rightExp) {
+        this.leftExp = leftExp;
+        this.rightExp = rightExp;
+    }
+
+    @Override
+    boolean resultWith(Map values) {
+        if (leftExp.resultWith(values)) {
+            return true;
+        } else {
+            return rightExp.resultWith(values);
+        }
+    }
+}