#210 Implemented single boolean expression

Author: ericbn

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

@@ -0,0 +1,20 @@
+package org.javalite.templator;
+
+import java.util.Map;
+import org.javalite.common.Convert;
+
+/**
+ * @author Eric Nielsen
+ */
+class BooleanId extends Exp {
+    private final ChainedIds chainedIds;
+
+    BooleanId(ChainedIds chainedIds) {
+        this.chainedIds = chainedIds;
+    }
+
+    @Override
+    boolean resultWith(Map values) {
+        return Convert.toBoolean(chainedIds.valueFrom(values));
+    }
+}

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

@@ -0,0 +1,55 @@
+package org.javalite.templator;
+
+import java.util.List;
+import java.util.Map;
+import static org.javalite.common.Inflector.*;
+
+/**
+ * @author Eric Nielsen
+ */
+class ChainedIds {
+    private final String firstId;
+    private final List<String> ids;
+
+    ChainedIds(String firstId, List<String> ids) {
+        this.firstId = firstId;
+        this.ids = ids;
+    }
+
+    private Object valueOf(Object obj, String id) {
+        try {
+            if (id.endsWith("()")) {
+                return obj.getClass().getMethod(id.substring(0, id.length() - 2)).invoke(obj);
+            }
+        } catch (Exception e) {
+            throw new TemplateException(e);
+        }
+        if (obj instanceof Map) {
+            return ((Map) obj).get(id);
+        }
+        try {
+            // try generic get method
+            return obj.getClass().getMethod("get", String.class).invoke(obj, id);
+        } catch (Exception e) {
+            try {
+                // try javabean property
+                return obj.getClass().getMethod("get" + capitalize(id)).invoke(obj);
+            } catch (Exception e1) {
+                // try public field
+                try {
+                    return obj.getClass().getDeclaredField(id).get(obj);
+                } catch (Exception e2) {
+                }
+            }
+        }
+        return null;
+    }
+
+    Object valueFrom(Map values) {
+        Object obj = values.get(firstId);
+        for (String id : ids) {
+            obj = valueOf(obj, id);
+        }
+        return obj;
+    }
+}

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

@@ -6,18 +6,57 @@
  * @author Eric Nielsen
  */
 class Comparison extends Exp {
-    private final Identifiers leftIdent;
-    private final Op op;
-    private final Identifiers rightIdent;
+    enum Operator {
+        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));
+            }
+        };
 
-    Comparison(Identifiers leftIdent, Op op, Identifiers rightIdent) {
-        this.leftIdent = leftIdent;
-        this.op = op;
-        this.rightIdent = rightIdent;
+        abstract boolean resultWith(Object obj1, Object obj2);
+
+        int compare(Object obj1, Object obj2) {
+            return ((Comparable) obj1).compareTo(obj2);
+        }
+    }
+
+    private final ChainedIds leftOperand;
+    private final Operator operator;
+    private final ChainedIds rightOperand;
+
+    Comparison(ChainedIds leftOperand, Operator operator, ChainedIds rightOperand) {
+        this.leftOperand = leftOperand;
+        this.operator = operator;
+        this.rightOperand = rightOperand;
     }
 
     @Override
     boolean resultWith(Map values) {
-        return op.resultWith(leftIdent.valueFrom(values), rightIdent.valueFrom(values));
+        return operator.resultWith(leftOperand.valueFrom(values), rightOperand.valueFrom(values));
     }
 }